These notes are intended to furnish a Student with information amply sufficient to enable him to pass the Honours Examination of the Science and Art Department, so far as a knowledge of Building Materials is concerned. They have, however, been extended somewhat beyond what is actually necessary for this purpose by the addition of Tables and information of a practical nature, which it is hoped may be useful to young Engineers, Architects, and others engaged in the design and erection of structures of different kinds.
Arranged To Meet The Requirements Of The Syllabus Of The Science & Art Department Of The Committee Of Council On Education, South Kensington
Advanced Course And Course For Honours
Second Edition. Revised And Enlarged
Notes On Building Construction- Arranged to meet the requirements of the Syllabus of the Science and Art Depart ment of the Committee of Council on Education, South Kensington. Medium 8vo, with 325 woodcuts, 10s. 6d. Part...
- Part III Materials
- Arranged to meet the requirements of the Syllabus of the Science and Art Department of the Committee of Council on Education, South Kensington. In Four Parts. Medium 8vo. Sold separately. Part I - ...
- Preface To Part III
- These notes are intended to furnish a Student with information amply sufficient to enable him to pass the Honours Examination of the Science and Art Department, so far as a knowledge of Building Mater...
- Note To Part III
- The following List contains the names of the books which have been referred to and consulted in the preparation of these Notes. Information derived from them has been acknowledged as far as possibl...
- Note To Part III. Continued
- Note For Students The Syllabus of the Science and Art Department contains the following particulars regarding the examination in materials: - 1 Examination for Second Stage or Advanced Course. ...
- Chapter I. Stone
- General Remarks In the following Notes no attempt will be made to describe the appearance and characteristics of all the different kinds of stone used in this country. Such a task would be almos...
- Charactestics Of Building Stone
- In selecting a stone for a building or engineering work, inquiry and investigation should be made to ascertain whether it possesses certain important characteristics mentioned below: - Durability, ...
- Charactestics Of Building Stone. Part 2
- Facility For Working The readiness with which stone can be converted by the mason into the various shapes in which it is required for different kinds of work is of importance from an economical poi...
- Charactestics Of Building Stone. Part 3
- Position In Quarry In order to obtain the best stone that a quarry can furnish, it is often important that it should be taken from a particular stratum. Fig. 1. Mould. ...
- Stone Seasoning
- Nearly all stone is the better for being seasoned by exposure to the air before it is set. This seasoning gets rid of the moisture, sometimes called quarry sap, which is to be found in all stone ...
- Agents Which Destroy Stones
- The two principal classes of agents which destroy stone have already been described. They are - Chemical agents, consisting of acids, etc., in the atmosphere; and Mechanical agents, such as wind, d...
- Examination Of Stone
- Speaking generally, in comparing stones of the same class, the least porous, most dense, and strongest, will be the most durable in atmospheres which have no special tendency to attack the constituent...
- Granite
- Granite is, as its name implies, a stone of crystalline granular structure. True Or Common Granite There are several varieties of stone practically known as granite, but true granite consists of...
- Granite. Continued
- Quarrying And Dressing Granite is quarried either by wedging or by blasting. The former process is generally reserved for large blocks, and the latter for smaller pieces and road-metal. It is be...
- Granite Varieties In Common Use
- Granite is found in Aberdeenshire, Kirkcudbrightshire, Argyleshire, and the Islands of Mull and Arran. Also in Cornwall, Devonshire, Leicestershire, Cumberland, and the islands of Guernsey and Jersey....
- Igneous Rocks Other Than Granite
- There are several rocke which more or less resemble the granite in their characteristics. and are generally associated with it in the classification of building stones. These rocks are, however, se...
- Trap Rocks
- Greenstone, also called Trap or Whinstone, is a mixture of felspar and horablende. It has isometimes a granular crystalline structure, and at other times it is very compact without apparent grains....
- Slates And Schists
- Clay Slate The ordinary slate used for roofing and other purposes is an argillaceous rock, compact and fine grained. It was originally a sedimentary rock, but it will no longer divide along the pla...
- Characteristics Of Slates
- Hardness And Toughness A good slate should be both hard and tough. If it is too soft it will absorb moisture, the nail holes will become enlarged, and the slate will be loose. If it be brittl...
- Characteristics Of Slates. Continued
- 1. Weigh the slate carefully when dry, steep it in water for 24 hours, run the water off, and weigh again - any difference of weight will show the amount of absorption. 2. Stand the slate in water ...
- Different Forms Of Slate. Slate Slabs
- Besides the small thin slates used for roofing, large and thick slabs, and even blocks of slate, are quarried out and used for many purposes connected with building and engineering works. Slate in ...
- Welsh Slates
- The finest slates found in the United Kingdom come from Wales. 1 Panworth. 657. 2 Wray. 3 Hunt's Handbook, Exhibition 1862. The slates from the Silurian formations of Merionethshire, Montg...
- Irish Slates
- Many of the best qualities resemble the Welsh varieties, others are thicker and coarser. Among the best known Irish roofing slates are those from Killaloe, or from the county Kilkenny Slabs of a hi...
- Stone Slates
- So called slates, being merely thin slabs of stone which splits into thin layers along the planes of bedding, are found in various parts of the country, and used for roofing purposes. They are tiles...
- Serpentine
- Serpentine derives its name from the mottled appearance of its surface, which is supposed to resemble the skin of a serpent. Composition Pure serpentine is a hydrated silicate of magnesia, but i...
- Sandstones
- Composition Sandstones consist generally of grains of quartz 1 Hull's Building and Ornamental Stones. 2 Report on the Geology of Cornwall, Devon, and Somerset, by Sir H. de la Becho. 3 Hul...
- Sandstones. Continued
- Thickness Of Layers In selecting sandstone for undercut work or for carving, care must be taken that the layers are thick; and it is of course important that stones should rest in most cases (see p...
- Bramley Fall
- The original stone known under this name was a moderately coarse-grained sandstone of the millstone grit formation, from Bramley, near Leeds. It held a very high character for durability and strength....
- Yorkshire Sandstones
- There are so many quarries producing stone of very similar quality and characteristics, classed under this head, that it would be useless to describe them in detail. These stones come chiefly from ...
- Scotgate Ash
- This stone is produced from quarries somewhat recently opened near Harrogate. Several specimens of it were shown at the International Exhibition of 1872. The quarries produce landings of any size u...
- Forest Of Dean Stone
- This very useful stone is found in the coal measures near Lydney and Coleford in Gloucestershire. There are three distinct series or beds of considerable thickness. Of these the upper series consis...
- White Mansfield
- There are several beds of this stone. The top bed of all has a coarser grain than the others. The second and third beds supply a very good fine-grained stone, fit for the finest ashlar work; while the...
- Craigleith Stone
- Craigleith Stone is perhaps the most durable sandstone in the United Kingdom. It consists of quartz grains united by a siliceous cement, with small plates of mica. It contains 98 per cent of silica an...
- Limestones
- The term limestone is applied to any stone the greater proportion of which consists of carbonate of lime; but the members of . the class differ greatly in chemical composition, texture, hardness, and ...
- Marbles
- Marble is the name practically given to any limestone which is hard and compact enough to take a fine polish. The name is frequently, however, erroneously applied to other stones, such as serpentin...
- Marbles. Part 2
- Table Of Some Of The Principal Marble Quarries In Great Britain And Ireland NAME OF QUARRY. NEAREST POST TOWN. COUNTY. COLOUR OF STONE. Weigh...
- Marbles. Part 3
- Table Of Some Of The Principal Continental Marble Quarries NAME OF QUARRY. COUNTRY. COLOUR OP STONE. Weight Per Foot Cube in Lbs. ...
- Compact Limestone
- Composition and Structure. - Compact limestone consists of carbonate of lime either pure or in combination with sand or clay. It is generally devoid of crystalline structure, of a dull earthy appea...
- Granular Limestones
- Composition and Structure. - These limestones consist of grains of carbonate of lime cemented together by the same substance, or by some mixture of carbonate of lime with silica or alumina. Size Of...
- Shelly Limestone
- There may be said to be two classes of this stone. Structure The first consists almost entirely of small shells cemented together, but shows no crystals on fracture. Purbeck is an example of ...
- Magnesian Limestones
- Composition. - Magnesian limestones are composed of carbonate of lime and carbonate of magnesia in variable proportions, together with a small quantity of silica, iron, and alumina. 1 Wray. Many...
- Magnesian Limestones. Continued
- Geological Position This stone is obtained from that division of the Oolitic formation which is known as the Great or Bath Oolitic group. Geologically speaking it lies below the Portland stone, bei...
- Quarries
- There are several quarries in the neighbourhood of Bath, among which may be mentioned the following: - Box Ground Found in beds from 10 inches to 4 4 1/2 feet thick. A coarse but sound stone, wh...
- Limestone Chemical Composition
- The chemical composition of the different varieties is almost the same, and it may therefore be given at once for the whole. The following is the analysis made by Professors Daniel and Wheatstone f...
- Chilmark Stone
- This stone is procured from the Portland and Purbeck series of the oolitic formation as developed near Tisbury, Wardour Castle, in Wiltshire. It is known also as Wardour stone, and in London as Tis...
- Chilmark Stone. Continued
- Beds The Ragstone is found in beds varying from 6 inches to 3 feet in thickness, alternating with fine sand known as Hassock, which is frequently so consolidated as to form a stone that can be used...
- Main Bridge
- Like the last bed, but of small scantling. Used for paving kerbs. After the last bed comes some inferior hassock. Garl yields hard blocks of considerable side, used for headstones. Upper and lower ...
- Main Bridge. Continued
- Table Of The Principal Limestone Quarries In Great Britain And Ireland NAME OF QUARRY. NEAREST POST TOWN. COUNTY. COLOUR OF STONE. Weight ...
- Artificial Stone
- In consequence of the difficulty which exists in many localities of obtaining durable natural stone at a moderate cost, many processes have been invented for the manufacture of artificial stone. So...
- Victoria Stone
- Victoria Stone consists of washed, finely-powdered granite, bound together with the strongest Portland cement, and then hardened by immersion in silicate of soda. The silicate is formed by boiling ...
- Chance's Artificial Stone
- Chance's Artificial Stone is made by melting the Rowley Rag, a basaltic rock found in Staffordshire, and then casting it into the shapes required for different architectural ornaments. Greenstone, ...
- Preservation Of Stone
- In consequence of the rapid decay of some of our public buildings (especially the Houses of Parliament), the question of the preservation of stone has of late years attracted much attention. Severa...
- Preparations Containing Organic Substances
- Filling the Pores with Organic Matter. - Paint. - One of the most common methods of preserving the surface of stone is to paint it. This is effectual for a time, but the paint is destroyed by atmosphe...
- Preparations Not Containing Organic Substances
- Soluble silica. - There is a large class of preparations whose preservative influences depend upon the presence of soluble silica, which combines with substances contained in, or added to the stone un...
- Other Processes
- Among other processes which have been tried are - Solution of Baryta followed by solution of Ferro-silicic Acid so as to fill the pores of the stone with an insoluble ferro-silicate of baryta. S...
- Tables Illustrating The Properties Of Different Stones
- The following Tables give a selection from the results of a great number of experiments upon stone made by various authorities. In many cases the figures given are not directly comparable with each...
- Tables Illustrating The Properties Of Different Stones. Part 2
- Resistance Of Stone To Crushing The following results are from Mr. Kirkaldy's experiments with 6-inch cubes: - Stone. Crushing Weight per Square Inch in Tons. ...
- Tables Illustrating The Properties Of Different Stones. Part 3
- Weight Of Stone A long list of stones, giving the weight per cubic foot of each, was prepared by Mr. C. H. Smith for the Mineral Statistics published at the Museum of Practical Geology. The info...
- Tables Illustrating The Properties Of Different Stones. Part 4
- Resistance To Wear Mr. Walker exposed the undermentioned descriptions of granite and whinstone to very heavy waggon traffic for seventeen months, and found their vertical wear to be as follows: - ...
- Chapter II. Bricks, Tiles, Terracotta, etc
- THERE are many different forms in which clay after it is burnt or baked is used by the builder and engineer. Some of the more important of these will now be described under the following classifica...
- Brick Earths
- Constituents Of Brick Earth The earths used for making ordinary bricks generally consist of alumina and silica, either alone or in combination with other substances, such as lime, magnesia, iron, e...
- Salt
- Common salt is nearly always present in minute quantity in clays; but when these are taken from the sea-shore, or without or beneath the sea-washes, or from localities in and about the salt formation...
- Practical Classification Of Brick Earths
- Brick earths are generally divided into three classes. 1. Plastic or Strong Clays (called by the brickmaker foul clays), which are composed of silica and alumina, with but a small proportion of l...
- Characteristics Of Different Kinds Of Brick Earth
- The quality of the bricks produced depends to a very great extent on the selection and mixing of the clay. Pure or Foul Clays are sometimes used for bricks without the addition of other substances....
- Brickmaking
- The operations involved in brickmaking are very numerous, though not intricate; they differ in several particulars in different localities, according to local custom, generally influenced by the natur...
- Brickmaking. Part 2
- Preparation Of Malm The clay is dug in the autumn and at once tipped, together with a proportion of ground chalk in pulp, into a wash mill. This consists of a brick-lined circular tank in which are...
- Brickmaking. Part 3
- Bearing Off As each brick is moulded it is disposed of in one of two ways - 1. It may be carried by a boy in the mould to the drying floor or ground, and there deposited, the mould being taken o...
- Brick Machine-Moulding
- When there is a large number of bricks to be made at the same spot, it pays to set up machines for moulding, and in cases where the clay is very hard, stony, or in any way refractory, machines become ...
- Brick Burning
- Bricks are burnt in clamps or in kilns according to the practice of the locality. 1 Dobson. 2 Except when they are to receive a layer of asphalte for a damp course. Clamp Burning Clamp...
- Quality Of Bricks
- The bricks taken from a clamp will be found very unequal in quality. Those from near the eyes are often fused together, or misshapen, forming burrs. Those near the outside are underburnt and soft, and...
- Kiln Brick Burning
- There are several descriptions of kilns used for burning bricks, but it will only be necessary to refer to those that are likely to be used by the engineer or builder in establishing a temporary brick...
- Comparative Advantages Of Kiln And Clamp Burning
- The following advantages are claimed for kiln-burning over clamp-burnino: - 1 Dobson. Plan. Fig. 11. Cross Section on A B. Fig. 12. 1. In kilns the bricks are nearly all turned out...
- Comparative Advantages Of Kiln And Clamp Burning. Continued
- Size And Produce Of Kiln Each chamber, if made about 36 feet long, 15 feet mean width, and 8 feet high, will hold 25,000 bricks. 12 x 25,000 = 300,000 bricks may therefore be burnt in the whole ...
- Classification Of Bricks
- Building bricks may, for the purposes of the engineer or architect, be divided into three classes. 1. Cutters or Rubbers, i.e. bricks intended to be cut or rubbed to some shape different from that ...
- Classification Of Bricks. Continued
- Classification Of Kiln-Burnt Bricks Kiln-burnt bricks are generally pretty equally burnt, and are classed chiefly according to the process by which they are made. Thus in one yard the classifica...
- Varieties Of Bricks In The Market
- The bricks used in ordinary buildings generally are, or should be, the best that are made in the neighbourhood. Some descriptions of bricks, however, are universally known, and are used even outsid...
- Varieties Of Bricks In The Market. Continued
- Black Bricks are obtained from Cowbridge in South Wales, from Maidenhead in Berkshire, and from other places. Some inferior black bricks are made with a mixture of soot, and are weak and almost use...
- Characteristics Of Good Bricks
- Freedom from Flaws or Lumps. - Good building brick should be sound, free from cracks and flaws, also from stones, or lumps of any kind. Lumps of lime, however small, are specially dangerous; they s...
- Method Of Distinguishing Clamp-Burnt, Kiln-Burnt, And Machine-Made Bricks
- - In clamp-burnt bricks the traces of the breeze mixed with the clay-can generally be seen. Kiln-burnt bricks very often have light and dark stripes upon their sides, caused by their being arranged...
- Tests For Bricks
- The best method of testing bricks is to see if they ring when struck together; to ascertain their hardness by throwing them on to the ground, or by striking them against other bricks. The fractured...
- Strength Of Bricks
- In practice bricks are subjected to compression, and sometimes to transverse stress, but not to tension. The compressive stress brought upon evenly-bedded bricks is generally far less than they are...
- Strength Of Bricks. Continued
- Transverse Strength Of Bricks The only records, known to the writer, of experiments on the transverse strength of bricks do not state how the weight was applied, so that they are valueless. Tens...
- Different Forms Of Bricks
- The different forms in which bricks are made for special purposes are almost innumerable. It would not be worth while, even if space were available, to describe them all; but a few of the principal...
- Different Forms Of Bricks. Continued
- Round-Ended And Bull-Nosed Bricks Figs. 28 and 29 are for use at corners where sharp arrises would be liable to damage. Splay Bricks are bevelled off on one side, like Fig. 30. They are sometime...
- Fireclay And Firebricks
- Fireclay is the name given to any clay which is capable of standing a high temperature without melting or becoming soft Such clays are also called refractory. Uses In Building Fireclay is requir...
- Fireclay And Firebricks. Continued
- Fireclay Grain It should be remarked that the infusibility of fireclays does not depend altogether upon their chemical composition, but also upon their degree of fineness. A fireclay with a coarse ...
- Terra Cotta
- Terra Cotta is a kind of earthenware which is rapidly coming into use as a substitute for stone in the ornamental parts of buildings. 1 Percy's Metallurgy, p. 238. 2 Mr. Baldwin Latham, Sanitary En...
- Terra Cotta Advantages and Disadvantages
- Terra Cotta Advantages The advantages of terra cotta are as follows: - Durability If properly burnt, it is unaffected by the atmosphere, or by acid fumes of any description. Lightness I...
- Terra Cotta Colour
- Terra cotta is made in several colours, depending chiefly upon the amount of heat it has gone through. White, pale grey, pale yellow, or straw colour indicate a want of firing. Rich yellow, pink...
- Where is Terra Cotta Used
- Terra cotta has been extensively used in Dulwich College, in Messrs. Doulton's warehouses, Lambeth, in the Albert 1 Proceedings R I.B. A. 1886, p. 129. 2 Reports on Exhibition, 1876, p. 14. H...
- Pipes And Miscellaneous Clay Wares
- Pipes and other articles made in clay are practically divided under four heads. 1. Unglazed Earthenware, made from ordinary clays, similar to those used for common bricks and tiles. Earthenware ...
- Glazing
- It is often advisable to glaze the surface of articles made in clay, sometimes for appearance, but more generally in order to protect portions exposed to the action of the atmosphere, to sewage, or ot...
- Terra cotta, stoneware, and fireclay Ware Burning
- Terra cotta, stoneware, and fireclay ware, are all burnt in domed kilns. The heat is applied gradually, and after it has risen to its height is kept up for a period varying from 24 to 72 hours, acc...
- Sewer Pipes
- Sewer Pipes should be of a vitreous imperishable material, of sufficient strength to resist fracture, having toughness enough to withstand shocks, tenacious, hard, homogeneous, impervious, uniform in ...
- Socket Pipes
- Pipes intended to convey sewage are generally made with sockets. Care should be taken that this socket is in the same piece with the pipe, not formed separately, as is sometimes the case. Half Sock...
- Socket Pipes. Continued
- Tests For Sewer Pipes The impermeability of a pipe maybe tested by tying a piece of bladder over one end, reversing it, and filling with water. If it is not perfectly impervious, the water will be...
- Miscellaneous Clay Wares
- The variety of articles used by the engineer and builder - which are made from burnt or baked clay - is endless. A few of the more important may now be mentioned. Perforated Air Bricks are made ...
- Bonding Bricks
- These bricks, introduced by Mr. Jennings, are used for uniting the opposite sides of hollow walls. The original bricks were straight. A sketch of one is given in Fig. 61. The improved bonding brick...
- Tiles
- The tiles used in connection with buildings may be divided into two great classes. 1. Common tiles of different shapes used for roofing and paving. 2. Encaustic tiles used for decorative purpose...
- Roofing Tiles
- Of these there are several different kinds, a few of which will now be described. Tile roof coverings are heavy; moreover they are apt to absorb water, and to keep the roof wet. To prevent this ...
- Wade And Cherry's Tiles
- These tiles are each shaped something like the ace of spades, so that their form renders the amount of lap smaller than in ordinary tiles. Fig. 78. Fig. 79. Fig. 80. A flange, ...
- Wall Tiles
- Hall's Hanging Tiles are glazed of different colours and fixed to walls by a nail in each tile driven into the joints of the brickwork, and are used to cover walls where light is important, as in area...
- Inferior Encaustic Tiles
- A class of pseudo-encaustic tiles is now being largely made, in which the colour, which should be burnt in along with the clay, is merely applied as a transfer printed pattern on the surface. Suc...
- Dry Tiles
- These tiles, each of which is of the same colour throughout, are made by the dry process. The clay having been very carefully prepared is mixed with the colouring matter, slipped, dried, and red...
- Chapter III. Limes, Cements, Mortar, Concrete, Plasters, And Asphaltes. Limes And Cements
- THERE are hardly any materials used by the engineer, architect, or builder, on which so much depends as upon mortar and concrete. There are differences of opinion on many points connected with the ...
- Constituents Of Limestone
- Constituents Of Limestones Which Do Not Produce Hydraulicity Carbonate of Lime.1 - As already noticed, some limestones, such as chalk and marble, consist entirely of this substance, and in all it p...
- Constituents Of Limestone Which Produce Hydraulicity
- The substances above noticed give the lime no hydraulic properties whatever. It is most important to understand distinctly what constituents are necessary in a limestone to confer upon it the chara...
- Soluble Silica
- There are several forms of silica, such as sand, flint, etc., which, as already noticed, are useless in lime, for they are only in a state of mechanical mixture with it. The silica must be in combinat...
- Classification Of Limes And Cements
- The calcined limestone is divided, according to its action in slaking and setting, into the following classes: - 1. Rich, Fat, or Pure Limes. 2. ...
- Classification Of Limes And Cements. Continued
- Rough Tests A few rough tests may be applied to a limestone to see if it is likely to furnish a hydraulic lime or cement. Such a stone will generally have an earthy texture, and will weather to ...
- Limes
- Rich or Pat Limes are those calcined from pure, or very nearly pure, carbonate of lime, not containing sufficient foreign constituents to have any appreciable effect upon either the slaking or setting...
- Stained Fat Limes
- Some of the lime which finds its way into the London market, under the assumed names of Dorking, Hailing, and Mers-tham, is merely fat lime tinged with iron sufficiently to give it the buff colour cha...
- Varieties Of Lime In Common Use
- Fat Limes. - White chalk, marble, the Oolitic limestones, and shells, when calcined, furnish the fat limes in ordinary use. A great variety of fat limes is found in England, Scotland, and Ireland. ...
- Cements
- The cements used in building and engineering works are calcareous substances, similar in many respects to the best hydraulic limes, but possessing hydraulic properties to a far greater degree. They...
- Natural Cements
- Natural cements are burnt direct from stones containing from 20 to 40 per cent of clay, the remainder consisting chiefly of carbonate of lime alone, or of carbonate of lime mixed with carbonate of mag...
- Market Farms
- Roman cement is usually sold in casks; sometimes, if it is to be used at once, in sacks. The inside dimensions of the casks are 2 feet 4 inches high, 1 foot 4 1/2 inches diameter at middle, 1 foot ...
- Artificial Cements
- Hydraulic cement is made artificially by a process similar to that already described for artificial hydraulic limes (see p. 155), a higher proportion of clay being added to make the mixture resemble t...
- Cement Manufacture From Chalk And Clay
- The cement best known in this country is made on the banks of the Thames and Medway, from chalk and clay mixed by the wet process. The proportion of chalk and clay mixed together depends upon the c...
- Cement Manufacture From Limestones And Clay Or Shale
- In some parts of the country the denser limestones are used in the absence of chalk for the manufacture of Portland cement: hard shales have also often to be used instead of clay. Thus the Warwicks...
- Portland Cement Made From Slag
- Ordinary blast furnace slag (see p. 259) contains nearly the same constituents as Portland cement, but not in the same proportions - the proportion of lime being too small. Mr. Ransome runs the molten...
- Tests Of Cement Quality
- A very slight difference in the manufacture may make a great difference in the character of the material, and rigid testing is necessary in order to secure the best cement. Before using Portland ce...
- Gauge Of Wire Of Sieves
- It is a curious thing that though many engineers specify the number of meshes to the square inch in the sieves to be used, very few mention the gauge of the wire of which the sieves are to be made, al...
- Cement Weight
- This particular is generally carefully ascertained. It used to be considered that a good weight per bushel was a sign of thorough burning, but it is now realised that the weight is greatly influenced ...
- Cement Specific Gravity
- Mr. Mann found1 that the specific gravity of cement supplied by the best English manufacturers slightly exceeded 3.0. The particles rejected by a sieve of 2900 meshes to the square inch had a speci...
- Rente's Specific Gravity Bottle
- This bottle consists of two bulbs, the lower somewhat exceeding the upper in capacity. The exact capacity of the lower bulb is of no importance. On the neck between the bulbs is a file mark b, on the ...
- Cement Colour
- This point should be examined, though it is not of very great importance. Bad cement may be of a good colour. Good Portland cement, as received from the manufacturers, should be of a grey or greeni...
- Test For Cement Tensile Strength
- This is the most important test in most cases, and it should be made with the aid of a proper machine, as hereinafter described (see p. 182). Seven Days' Test The tensile strength of Portland ce...
- Test For Cement Tensile Strength. Part 2
- Thirty Days' Test It will be noticed that most of the tests above mentioned are applied seven days after the cement is gauged and formed into a briquette. It has, however, often been suggested t...
- Test For Cement Tensile Strength. Part 3
- Testing By Compression Again it has been pointed out that cement when in actual use is generally subjected to compression - very rarely to tension - and that it would be more useful to test its res...
- Cement Adhesive Strength
- Yet another objection is made to the method of testing hitherto and still adopted by most engineers. It is pointed out that, as the principal function of cement is to produce adherence between port...
- The Briquette
- The tensile stress that a cement will bear depends greatly upon the manner in which the test is made, the form of briquette, the method in which the cement is gauged, the amount of water used, etc. et...
- Nature And Proportion Of Water In Cement Mortar
- No more water should be used than is necessary to make the cement fit for use, an excess produces porosity and retards the process of hardening. Grant's experiments show that with 19 per cent of wa...
- Shape Of Briquette
- The cement to be tested is formed into a briquette shaped in one of the forms shown in section in Figs. 83 to 86. 1 Grant, M.P.I.C.E, vol. lxii. p. 124. 2 Grant, M.P.I.C.E. 1880, vol. lxii. p. 158....
- Tests For Cement Coolness
- In some cases cement which appears perfectly good in every way has a tendency to crack and swell when placed under water. This action, which is commonly known as blowing, is caused by the cement be...
- Additional Tests For Portland Cement
- Besides the ordinary tests above mentioned, the following rough tests will give an indication as to some important qualities of the cement before using it. 1. A bottle is filled with paste made fro...
- Cement Hardening And Setting
- It is important to know how long a cement takes to harden and set. This is generally roughly ascertained by the impression of the finger nail upon the cakes of cement, as described on page 172, but as...
- Cement Storing
- Portland cement is generally received in sacks in this country, in casks abroad; these should at once be emptied,the cement spread out for a month or so on a wooden or concrete floor, to a depth not e...
- Cement Strength
- The strength of Portland cement varies, as has already been mentioned, according to its original composition as regards the percentage of chalk and clay used in its manufacture, with the degree of bur...
- Cement Strength. Part 2
- Remarks This Table shows (1) that the coarsely ground cement broke at a higher point when used neat than when finely ground or sifted, but at a much lower point when mixed with sand: (2) that at 25...
- Cement Market Forms
- Portland cement is sold in casks or in sacks for home consumption, and in casks for export. The inside dimensions of the casks are sometimes as follows, but they vary. Length, 27 1/2 inches. Diamet...
- Selenitic Cement. Selenitic Lime
- Selenitic Cement,2 sometimes known as selenitic lime, is also an invention of General Scott's. This cement, like the other, contains a small proportion of sulphate of lime, which is added in the fo...
- Pozzuolana Mortars
- These are formed by adding to ordinary fat lime or feebly hydraulic mortars such a proportion of pozzuolana (see p. 196) as will make good their deficiency in clay. This proportion depends upon the co...
- Means For Testing Tensile Strength Of Cement
- It has already been mentioned that the tensile strength of Portland cement for important works should always be tested by direct experiment. There are several different machines by means of which t...
- Adie's Cement Tester With Automatic Register
- In order to arrange for a uniform speed, Mr. Adie has added an automatic regulator to his machine, which is shown in Fig. 88b. Fig. 86. Cement Tester, with Patent Automatic Regulator. Patent...
- Michaells's Double Lever Cement Testing Apparatus
- Michaelis's Double Lever Cement Testing Apparatus, Figs. 90 and 90re. - Makers Directions. - This apparatus consists of a japanned cast iron column, which carries two levers, the combined leverage of ...
- Faija's Cement Testing Machine
- Faija's Testing Machine is shown in Fig. 92, from the patentee's circular. The ordinary-sized machine adapted to briquettes of 1 square inch section will test from 1 to 1000 lbs. The machine is 14 ...
- Reid and Bailey's Cement
- Tester is shown in elevation in Fig. 93, which is taken from the makers' circular.1 The briquette having been inserted in the clips c c holds down the short arm of a straight lever. The long arm...
- Simple Tests Without Machines
- A tank of water suspended from the specimen may be used as a good simple method of testing the tensile strength. The weight in lbs. at different depths can be marked inside the tank. The following ...
- Adulterations In Portland Cement
- It is stated in the circulars of some cement manufacturers that iron slag is used for the adulteration of Portland cement. If this is suspected, the only way to avoid it is to refuse to take cement fr...
- Lime And Cement Burning
- Limestone is calcined (burnt into lime) in clamps or in kilns of different forms. Clamps consist merely of heaps composed of alternate layers of limestone and coal, having a fire-hole below, ...
- Lime And Cement Burning. Continued
- Portland Cement Kilns (Common Form) Fig. 99 is the section, and Fig. 100 an elevation, of a form of kiln commonly used for burning Portland cement in the Medway district. Fig. 99. Section. ...
- General Remarks On Burning
- Gradual heating is necessary in burning lime or cement stone. If the heat be suddenly applied, the carbonic acid and moisture will be driven out with such violence as to blow the stone to pieces. A...
- Dangerous Limes And Cements
- Sometimes, from defects in the process of calcination of a stone which should produce an eminently hydraulic lime or cement, compounds result which are of a most dangerous character. These are caus...
- Sand And Substitutes For Sand
- Sand is known as argillaceous, siliceous, or calcareous, according to its composition. It is procured from pits, shores of rivers, sea-shores, or by grinding sandstones. It is chiefly used...
- Pozzuolanas, etc
- Pozzuolana is a name given to several substances which somewhat resemble each other; including the Pozzuolana proper, also Trass, Arenes, Psammites, etc. These are clayey earths containing 80 to 90...
- Mortar
- Ordinary Mortar is composed of lime and sand mixed into a paste with water. When cement is substituted for the lime, the mixture is called Cement Mortar. Uses The use of mortar in brickwork o...
- Evils Of Fat Lime Mortar
- If a pure or feebly hydraulic lime mortar is used in massive brickwork or masonry, it is only the outer edges of the joints that are affected by the carbonic acid in the air. A small portion of the ex...
- Description Of Sand To Be Used In Mortar
- Sand is used in mortar to save expense and to prevent excessive shrinkage. Ordinary sands are not in any way chemically acted upon by the lime, but are simply in a state of mechanical mixture with ...
- The Description Of Water To Be Used In Mortar
- The water used for mixing mortar should be free from mud, clay, or other impurities. Salt Water is objectionable in some situations, as it causes damp and efflorescence. Salt Water is objectiona...
- Strength Of Mortar As Compared With Bricks In A Wall
- Lime is much more expensive than sand. It is, therefore, a source of economy to add as much sand as is possible without unduly deteriorating the strength of the mortar. So long as the joints of mas...
- Mortar Ingredients Preparation And Mixing
- The quicklime and sand having been procured, and their proportions decided, the preparation of the ingredients commences. Slaking A convenient quantity of the quicklime is measured out on to a w...
- Mortar Ingredients Mixing
- The great object in mixing is to thoroughly incorporate the ingredients, so that no two grains of dry sand should lie together without an intervening layer or film of lime or cement. On extensive w...
- Bulk Of Mortar Produced
- The bulk of mortar produced in proportion to that of the ingredients differs greatly according to the nature of the lime or cement and the quantity and description of the sand added to it The more ...
- Bulk Of Mortar Produced. Continued
- The Use Of Sugar In Mortar It was pointed out many years ago 1 that the bad qualities of rich limes may be in some degree corrected by the use of a comparatively small quantity of the coarsest su...
- Selenitic Mortar Made With Ordinary Lime
- A few years ago persons using selenitic mortar were permitted to add the sulphate of lime for themselves, and where selenitic cement is not procurable the process might still be useful. It is condu...
- Portland Cement Mortar With Large Proportion Of Sand
- Mortar composed of 1 Portland cement, 8 sand, and 1 of slaked fat lime is much better and generally cheaper than 1 of grey lime to 2 sand - the slaked lime slightly weakens the mortar, but is necessar...
- Concrete
- Concrete is an artificial compound, generally made by mixing lime or cement with sand, water, and some hard material, such as broken stone, gravel, burnt clay, bits of brick, slag, etc. etc. These ...
- Concrete. Part 2
- Packing In building walls, or other masses of concrete, large pieces of stone, old bricks, chalk, etc., are often packed in for the sake of economy. Care should be taken that the lumps thus inse...
- Concrete. Part 3
- Mixing As before mentioned, the materials are generally mixed in a dry state, not upon the bare ground, but upon a clean timber or stone platform. The proportions decided upon are measured out eith...
- Concrete Laying
- Concrete should, after thorough mixing, be rapidly wheeled to the place where it is to be laid, gently tipped (not from a height) into position, and carefully and steadily rammed in layers about 12 in...
- The Cementing Material To Be Used For Concrete
- It is hardly necessary to say that when there is a choice the strength and quality of the cementing material should be in proportion to the importance of the part the concrete has to play. Thus fat...
- Bulk Of Concrete Produced
- The bulk of concrete obtained from a mixture of proper proportions of cement, sand, and aggregate, varies considerably according to the nature and proportions of the materials and method of treatment;...
- Selenitic Concrete
- Concrete may be made with selenitic cement mortar as the matrix. Portland cement is sometimes added in small quantities to the selenitic cement. From a series of experiments made on behalf of ...
- Uses Of Concrete
- Concrete has long been used for the foundations of structures of all kinds, and for filling in the spandrils of arches or the hearting and backs of walls. Of late years, as the material has improve...
- Strength Of Concrete
- Concrete blocks 12 inches cube, made of Portland cement, weighing 110.56 lbs. per bushel. This cement (neat) broke under a tensile stress of 427 lbs. per square inch after seven days' immersion in wat...
- Mortar-Mixing And Concrete-Mixing Machinery
- Mortar-Mixing Machines Mortar-Mill driven by Steam Power. - A full description of the different machines in use for mixing mortar would he out of place in these Notes, but a glance at one or two of...
- Portable Mortar-Mill
- For smaller works, and those which are scattered - as, for instance, along a line of railway - a portable mortar-mill may be used (see Fig. 104). This machine somewhat resembles the one last descri...
- Concrete-Mixing Machines
- Concrete can be thoroughly well mixed by hand in small quantities; but when large quantities have to be dealt with, it is difficult, without good organisation, discipline, and very close superintenden...
- Inclined Cylinder Machine
- A simple form of concrete-mixer consists in an inclined hollow iron cylinder mounted as shown in Fig. 107. The ingredients of the concrete are filled in by the aid of a hopper through a door at eit...
- Messent's Patent Concrete-Mixer
- The following description of this machine and the illustration Fig. 108, are taken from the circular of the makers, Messrs. Stothert and Pitt of Bath. It consists of a closed box or chamber, A, r...
- American Concrete-Mixer
- This machine consists of a long box or shoot divided vertically into compartments separated from one another by doors. The ingredients are placed in the uppermost compartment, and the doors being o...
- On The Action Of Foreign Constituents In Limestones And Cements
- The following is an attempt to convey some information with regard to the peculiarities connected with the burning, setting, etc., of limes, cements, and mortars of different classes. The subject i...
- Pure Or Pat Limes
- From the experiments made with limes of which the composition is accurately known, it is evident that the differences in their slaking and setting properties are due to the nature and proportion of th...
- Mortar Made From Fat Lime
- It has before been pointed out that the addition of sand improves the setting of fat limes - 1. Because the porous structure caused by the presence of the sand enables the carbonic acid of the air ...
- Hydraulic Limes And Cements Containing Clay
- With a lime containing clay the action is different from that of a pure lime, and not quite so simple. Before attempting to explain this action it will clear the ground to make a few remarks regard...
- Calcination
- When a limestone containing clay is burnt, the carbonic acid from the carbonate of lime and the water from the clay are partially or wholly driven off, and the ingredients are re-arranged in a new set...
- Proportion Of Clay
- Effect in Stones burnt at a moderate temperature. - If the stone contain a large proportion of clay and is burnt at a moderate temperature, the silicic acid in the clay attacks the lime, forming calci...
- Effect In Cements Burnt At A High Temperature
- When, however, the calcination is carried to a further stage, and the stone is burnt at a very high temperature, not only is the carbonic acid driven off and some of the lime converted into silicate o...
- Composition Of Clay
- If the clay contains a large proportion of iron and alumina (especially of iron) as compared with the silica, the calcination must be at a comparatively low temperature, or the particles will be fused...
- Effects Caused By Different Degrees Of Calcination
- It has already been pointed out that the temperature at which the calcination is affected greatly influences the nature of the hydraulic lime or cement produced. As a general rule slight calcinatio...
- Slaking
- This action also is influenced by the proportion of clay contained in the lime. 1 General Scott; R.E. Corps Papers, vol. xi. If the burnt stone contains so small a proportion of clay that the si...
- Setting
- We see, then, that after the processes of burning and slaking hydraulic limes containing clay, there is left within them a mixture of pure lime and silicates, or of pure lime, silicates, and aluminate...
- Pozzuolana, Etc
- As before noticed, the presence of several other forms of soluble silica and pozzuolana will also answer the purpose in a greater or less degree. The general nature of the reactions that take place...
- Carbonate Of Magnesia
- Carbonate of magnesia is a substance very similar to carbonate of lime; it loses its carbonic acid in burning, combines with silica, etc., and behaves generally in the same way, with one important exc...
- Efflorescence On Walls
- The surfaces of walls are often covered with an efflorescence of an unsightly character. This efflorescence is formed by a process known as saltpetreing. It shows itself chiefly in the case of newl...
- Analysis Of Limes And Cements
- The strictly chemical view of this subject is beyond the scope of these Notes; but in order to render them more complete, the following directions3 for testing and analysing a lime or cement are added...
- Plasters, Etc
- Materials Used By Plasterers A great variety of compositions are used by plasterers, some of which will be described. Among the most important of these are cements of various kinds. Many of thes...
- Plaster Uses
- The Keene's, Parian, and similar cements or plasters are largely used for the best class of internal plastering, and, as they set very quickly, they can be painted within a few hours, which is a g...
- Hair used by Plasterers
- The hair used by the plasterer in order to make his coarse stuff hang together is obtained from the tanner's yard. It should be long, sound, free from grease and dirt, thoroughly separated, beat...
- Stucco
- This term is very loosely applied to various substances which differ considerably from one another. These may be classed as follows: - 1. Compounds of hydraulic lime, formerly much used for external c...
- Plaster Enrichments
- The plasterer requires a great variety of mouldings, ornaments, pateras, flowers, and other enrichments for the decoration of his work. These may be made either in plaster of Paris composition or i...
- Asphaltes
- Asphaltes are combinations of bitumen and calcareous matter, sometimes found in nature, sometimes artificially formed. Natural asphaltes are superior to artificial imitations, probably because in t...
- Mixing Asphalte
- The blocks of asphalte are broken up into pieces of not more than 1 lb. weight each, and melted in iron caldrons heated by wood or peat. Coal is objectionable on account of the smoke it creates; co...
- Asphalte Making Liquid Process
- The material used is composed of Val de Travers rock, mixed with a large quantity of clean grit about the size of a split pea. The asphalte is melted in boilers as above described, a small quantity...
- Whitening And Colouring
- Whitewash is made from pure white lime mixed with water. It is used for common walls and ceilings, especially where, for sanitary reasons, a frequent fresh application is considered preferable to ...
- Quantity Of Materials Used For Plastering, Etc
- The quantity of materials required for plastering, rendering, etc., depends upon the nature of the materials used, the degree of roughness of the walls, and other circumstances. Information on this su...
- Chapter IV. Metals
- THE metals used by the engineer and builder are iron, copper, lead, zinc, tin, and some of their alloys. Ores These metals are not found to any great extent in the pure metallic state, but chief...
- Iron
- Production Ores. - Iron ores are generally carbonates, hydrates, or oxides of the metal, the latter being the best. British iron is obtained from ores found in several strata, but chiefly in tho...
- Smelting
- The extraction of the metal from the ore is effected in a large upright furnace lined with firebrick. Into this furnace a strong blast of air is forced. In former years the air for the blast was...
- Comparative Advantages Of Hot And Cold Blast Iron
- The very high temperature produced by the hot blast enables many of the impurities in the ore to be reduced to a molten state, and run out with the metal. If this is taken advantage of, the impurit...
- Pig-Iron
- Pig-iron is the name given to the rough bars of unpurified cast iron run from the blast furnace. In this form it is sold to the founder or to the iron manufacturer. By them it is subjected to va...
- The Effect Of Carbon Upon Cast Iron
- There are many varieties of pig-iron, which themselves also differ pretty much according to the proportion of carbon contained by them. These differences depend upon the quantity of fuel used in th...
- Impurities In Pig-Iron
- The impurities mentioned below are originally derived either from the ore or fuel, and unless eliminated in subsequent processes, they will injure the respective metals produced in the manner stated. ...
- Bessemer Pig
- A distinct variety of pig-iron made from haematite ores for conversion by the Bessemer process (see p. 304). It should be as free as possible from sulphur, phosphorus, or copper; but a small percentag...
- Cast Iron
- Cast Iron is obtained by remelting the foundry pig-iron of commerce, and running it into moulds of the shape required as hereinafter described. In some cases the metal is run into the moulds direct...
- Chilled Iron
- It is sometimes advisable to produce a casting, some parts of which are required to have the hardness of white iron, while others are required to be of the toughest grey iron. This effect may be pr...
- Descriptions Of Pig-Iron For Castings
- Great experience is required in order to know exactly what descriptions of pig-iron to choose in order to make castings for any particular purpose. Mixtures of pigs classed under different numbers,...
- Castings
- The description of the art of the ironfounder does not come within the range of these Notes. The few remarks which follow are intended only to give such a general idea of the process of ironfoundin...
- Casting In Loam
- Large pipes and cylinders are cast in a somewhat different way. A hollow vertical core of somewhat less diameter than the interior of the proposed cylinder is formed either in metal or brickwork. ...
- Form Of Castings
- The shape given to castings should be very carefully considered. All changes of form should be gradual. Sharp corners or angles are a source of weakness. This is attributed to the manner in which t...
- Examination Of Castings
- In examining castings, with a view to ascertaining their quality and soundness, several points should be attended to. The edges should be struck with a light hammer. If the blow make a slight impre...
- Tests For Cast Iron
- For small girders and other castings intended to carry weight, it is usual to test a certain proportion of the number supplied by loading them till they break, and noting the weight under which they g...
- Wrought Iron
- Wrought Iron is, or should be (as before mentioned), very nearly the pure metal, containing not more than about 0.15 per cent of carbon. It may, by a peculiar process, be procured direct from the o...
- Shingling
- The lumps or balls formed in the puddling furnace are at once placed under a helve or a tilt-hammer, the blows of which force out the cinder and consolidate and weld the particles of iron together, fo...
- Rolling
- Directly after this the red-hot slab of iron, or bloom, is passed between grooved rollers, which convert it into puddled bars about 3 or 4 inches wide, 3/4 to 1 inch in thickness, and 10 or 12 feet ...
- Effect Of Rolling Iron
- All wrought iron, after fusion, or after having been exposed to high temperatures sufficient to induce softening or pastiness, which is the case when iron is reheated to a white heat, consists of an a...
- Different Qualities Of Bar Iron
- The products of the rolling process are classified as follows: - Puddled Bars, also known as No. 1 or rough bars. The puddled bar obtained by the processes above described is of a very weak and ...
- Manufacture Of T And I Iron
- In manufacturing iron of T, I, or other sections, or rails, a pile of bars is formed, heated, and welded together under a steam hammer. This is then rolled, in the roughing or cogging rolls, into a...
- Tests For Wrought Iron
- General Remarks There are several ways in which the quality of a piece of wrought iron may be ascertained. It may be broken by direct slow tension, or by a falling weight, the breaking stress, e...
- Iron Uniformity
- In choosing iron for railway bridges and similar structures it is not only important that the iron should be strong and tough, but also that it should be uniform in quality. Iron structures should ...
- Unwin's Iron Bridges and Roofs
- Testing Machines The machines for accurately testing iron and steel are too cumbrous and expensive for ordinary use. Engineers generally send their specimens to be tested by Mr. Kirkaldy of Southwa...
- Swedish Bars
- Ultimate Stress per square inch. 22 tons. Contraction of area at fracture. Comparing this Table with the Tables of strength given at page 318, it will be seen that The best Yorkshire iron ...
- Swedish Bars. Continued
- Admiralty The Admiralty Tests for iron for ship-building may be tabulated as follows: - Tensile Strain per square inch. BB or 1st class plate iron ...
- Appearance Of The Fractured Surface Of Wrought Iron
- At one time it was thought that a fibrous fracture was a sign of good tough wrought iron, but that a crystalline fracture showed that the iron was bad, hard, and brittle. Mr. Kirkaldy's experiments...
- Different Descriptions And Market Forms Of Wrought Iron, And Their Relative Value. Descriptions Of Wrought Iron
- The following are the different kinds of wrought iron most generally known in this country. Swedish Iron is made from pure magnetic iron ore - chiefly from Danne-mora - smelted with charcoal. It...
- Market Forms Of Wrought Iron
- Wrought Iron is prepared for the market in several convenient forms. Ordinary Dimensions are those generally made and kept in stock. Everything required of different dimensions from these must be p...
- Angle And T Irons
- Iron of these sections is most useful in a great many building and engineering structures, such as roofs, girders, bridges, etc. etc. The sections are made of a great variety of dimensions. Iron me...
- Angle And T Irons. Part 2
- Rail Bars These are made, of various sections; some of them may be illustrated, but need not be described. Figs. 132. 133. 134. 135. 135a. Double-headed Rail (...
- Angle And T Irons. Part 3
- Extras Large or heavy plates are more expensive because they require more care and labour in manufacture. The extras charged upon plates vary slightly in the different districts, as will be seen...
- Mallet's Buckled Plates
- These are plates of any shape in plan, arched from the edges towards the centre; the arch has a very slight rise, and forms a dome or groined surface, according as the plate is round or square. Suc...
- Relative Value Of Different Descriptions And Forms Of Wrought Iron
- The price of iron of all kinds fluctuates continually according to the state of the market. These Notes do not profess to deal with the cost of materials; and the following lists are given merely to s...
- Hoop Iron
- Ordinary widths and gauges are as follows: - Inches. 3 3/4 to 6, not thinner than No. ...
- Hoop Iron. Continued
- Large Flats 3 1/4 to 4 in. by 2 1/2 to 3 in. . 10s. per ton. 4 1/4 ,, ...
- Flats, Bounds, And Squares, Where Not Extra For Size
- For every half-cwt. over 5 cwt., 10s. per ton. Common quality of Rounds, Machine-straightened, 10s. per ton. For Ovals, twice the extra, and for Half-ovals, three times the extra on above sizes ...
- Flats, Bounds, And Squares, Where Not Extra For Size. Continued
- Round And Square Per ton extra. 7/16 in. . . 10s. 3/8 ,, . 20s....
- Plates
- Ordinary sizes up to 15 by 4 feet, or 8 cwt. per plate. Best and Best Best above 6 cwt., Best, Best, Best above 4 cwt. ......... 20s. per ton. 5/16 and under 1/4 inc...
- Brands On Iron. Pig-Iron Brands
- The different pig-irons in the market are distinguished by brands, which indicate the locality from which the iron was procured. The brands, which are in raised letters on the pig, serve as a guide...
- Wrought Iron Brands
- In order to understand the different qualities of British wrought iron in the market, the relative cost of the different forms, and to form some idea of the brands by which they are distinguished, it ...
- Staffordshire Brands
- It will be seen that these irons are divided into three classes, which are (putting them in order of price) list brands, good marked iron, and common iron. List Brands are those used by some of the...
- Midland And Other Districts
- The remarks upon the iron manufactured by the less known makers in Staffordshire apply also to the qualities of iron priced in this column of the Table, page 290. is the brand used by the Midla...
- Steel
- Steel has been defined by Dr. Percy as iron containing a small percentage of carbon, the alloy having the property of taking a temper; and this definition is substantially equivalent to those found i...
- Characteristics Of Steel
- Hardening. - The characteristic difference between steel and pure wrought iron is as follows: - When steel is raised to a red heat and then suddenly cooled, it becomes hard and brittle. This proces...
- Amount Of Carbon In Steel
- It has already been stated that the peculiarities of cast iron, wrought iron, and steel are caused by the difference in the amounts of carbon which they respectively contain. Pure wrought iron cont...
- Varieties Of Steel. Methods Of Making Steel
- Steel may be produced either by adding carbon to wrought iron, or by partially refining pig-iron, thus removing a portion of its carbon until the proper amount only remains. There are several ways ...
- Shear Steel, Sometimes Called Tilted Steel
- By the process of cementation just described, the exterior only of the bars is carbonised. To produce steel of uniform quality throughout its mass, bars of blister steel are cut into short lengths; th...
- Cast Steel
- There are several ways of producing cast steel, some of which will now be mentioned. The ingots produced by any of these processes generally contain cavities. In order to get rid of these, they are...
- Bessemer Process
- By this process steel is made from pig-iron. The whole of the carbon is first removed so as to leave pure wrought iron, and to this is added the precise quantity of carbon required for the steel Th...
- Siemens' Process
- In this process pig-iron and ore are the ingredients employed to produce steel by fusion upon the open hearth of a regenerative gas furnace. The pig metal is first melted upon the hearth of the furnac...
- Siemens-Martin Process
- In another important modification of the same process, which is known generally as the Siemens-Martin Process, a bath of highly-heated pig metal is prepared in the furnace, and three or four times its...
- Whitworth's Compressed Steel
- It has already been stated that ordinary steel, as first cast, is porous, full of email cavities, which have to be removed by hammering before a sound metal is produced. In order to remedy this evi...
- Hardening Steel
- It has already been mentioned that steel plunged into cold water when it is itself at a red heat becomes excessively hard. The more suddenly the heat is extracted the harder it will be. This proces...
- Table Of Temperatures And Colours
- The following Table shows the temperature at which the steel should be suddenly cooled in order to produce the hardness required for different descriptions of tools. It also shows the colours which in...
- Different Methods Of Heating
- There are several ways of heating steel articles both for hardening and tempering. They may be heated in a hollow or in an open fire, exposed upon a hot plate, or in a dish with charcoal in an oven...
- Cooling
- When the whole bulk of any article has to be tempered, it may either be dipped or allowed to cool in the air. It matters not which way they become cold, providing the heat has not been too suddenly a...
- Blazing
- Saws are hardened in oil, or in a mixture of oil with suet, wax, etc. They are then heated over a fire till the grease inflamee. This is called being blazed.. After blazing the saw is flattened ...
- Tests For Steel
- Steel to be used in important work should be tested as to its strength, ductility, and other qualities. The methods of testing are similar to those adopted for wrought iron and described at p. 276. ...
- Tests For Steel. Continued
- Percussive Test For Round Bars A specimen bar of 2 diameter is taken, when required by the overseer, from every charge, or from every 50 bars or portions of 50, and subjected to a percussive test....
- Market Forms, Relative Value Of Different Kinds, And Brands On Steel
- Market FORMS - Steel may be obtained in most of the forms adopted for wrought iron, and described at page 284. Angle and T of all sizes up to 4 inches x 4 inches are easily obtained, but many sections...
- Market Forms, Relative Value Of Different Kinds, And Brands On Steel. Continued
- Extras On Steel Plates The following list gives the extras upon steel plates, but steel is generally sold to specification, as so much depends upon the proportion of different sizes: - ...
- Brands On Steel
- There are no list brands for steel (see p. 296). Each maker has his own trade mark, generally the name of his firm, with or without name of his work. Thus - (Atlas), Jno. Brown and Company, Limited; (...
- Crucible Cast Steel
- The ingots have each a paper label attached, on which is marked the purpose for which the steel is best adapted, as follows - borer, welding, tool, rivet. Shear and Double Shear steel bars are mark...
- Strength Of Cast Iron, Wrought Iron, And Steel
- It is beyond the province of these Notes to enter upon the general subject of the physical properties of materials. The meanings of a few of the terms used in connection with those properties are give...
- Ultimate Strength And Ductility
- The tests which are applied in practice to cast iron, wrought iron (of different classes), and steel, have been described in previous pages. In order to apply these tests intelligently, it is neces...
- Strength of Cast Iron
- The average ultimate strength of the ordinary varieties of cast iron found in the market may be taken as follows: - Tons per Square Inch. Tension 6...
- Repeated Remeltings
- Repeated remelting of cast iron increases its strength, probably in consequence of the carbon being burnt out of it, thus tending to assimilate it in composition to wrought iron. Sir William Fairbairn...
- Effect Of Temperature
- Sir William Fairbairn's experiments led him to the following conclusion: - Cast iron of average quality loses strength when heated beyond a mean temperature of 120, and it becomes insecure at th...
- Strength and Ductility of Wrought Iron
- The strength and ductility of wrought iron depend upon the quality of the material and the care with which it is manufactured. A very small proportion of carbon is practically always present; if th...
- Tensile Strength
- The following Table shows the tensile strength,, contraction of area and elongation after fracture, ascertained by experiments upon some of the more important descriptions of iron found in the market....
- Tensile Strength. Continued
- Effect Of Temperature Sir William Fairbaim found that the strength of wrought iron was practically the same at all temperatures between 0. and 400 Fahr.6 1 Kennedy, Iron, 11th May 1883. 2 I...
- Average Strength
- The great differences in strength caused by varieties in the amount of carbon and in temper make it useless to attempt to arrive at an average strength for all steels. The following may be taken as...
- Tensile Strength and Ductility of Steel Plates With and Against the Grain. From Mr. Kirkaldy's Experiments
- L. signifies lengthways of the grain; C. across the grain. Names of Makers or Works. Thickness. Description. Tearing weight per square inch of original ...
- Tensile Strength and Ductility of Steel Plates With and Against the Grain. Continued
- Tensile Strength and Ductility of Steel Bars. Selected from Mr. Kirkaldy's Experiments.2 Names of Makers or Works. Description. Average breaking weight per square ...
- Landore Steel
- Tensile Strength and Ductility. - The mean breaking tensile stress for 101 samples of plates and angle irons, as given by Mr. Riley, was 28.16 tons per square inch, and the elongation 24.25 per cent. ...
- Shearing Strength Of Steel
- Mr. Kirkaldy's experiments led him to the following conclusion: - The shearing strain of steel rivets is found to be about a fourth less than the tensile strain.5 The steel he experimented upon ...
- Effect Of Different Processes And Circumstances Upon The Strength Of Steel
- Effect of Tempering. - After a series of experiments Mr. Kirkaldy came to the following conclusions as to the influence upon steel caused by its treatment in different ways. 35th. Steel is reduced...
- Influence, Of Carbon Upon Strength Of Steel
- The following Table1 contains the relation between the specific gravity and tensile strength of Bessemer steel of various degrees of carbonisation, made at Sandriken, in Sweden: - Perce...
- Safe Or Working Stresses For Cast Iron, Wrought Iron, And Steel
- The limiting or working stresses that can be safely applied in practice to cast iron, wrought iron, and steel respectively, depend not only upon the quality and characteristics of the material, but up...
- Working Stresses
- The following working stresses may be used in practice: - Cast Iron. - For girders, etc., to carry a dead load - Compression 8 tons per square inch. ...
- Board Of Trade Rule
- Though the construction of bridges is a subject entirely beyond the limits of any part of these Notes, it may be as well to mention here the Board of Trade rule as to the working stress for bridges, b...
- Opinion Of Committee Appointed By The Board Of Trade
- The use of steel in railway bridges and other structures is not at present provided for by the Board of Trade regulations, and hence the working stress per square inch to which it may be submitted is ...
- Limit Of Elasticity
- In investigating the properties of a specimen of iron or steel a very important point to be ascertained is its limit of elasticity. The meaning of this term has been defined in several different wa...
- Fatigue Of Iron
- Many careful experiments made by Sir W. Fairbairn and others have led to the conclusion that a load may be applied to a wrought iron bar, removed and reimposed thousands of times without the slightest...
- False Permanent Set
- In some cases, after imposing upon a bar a load far within the elastic limit, a permanent set seems at first to have been caused, but upon leaving the bar unloaded for a short time this set disappears...
- Other Definitions Of The Limit Of Elasticity
- It should here be mentioned that Mr. Eaton Hodgkinson's experiments led him to the conclusion that the very smallest load produces a permanent set. His conclusions have been questioned by more recent ...
- Live And Moving Loads
- To consider the effect of moving and live loads upon the strength of iron and steel would open up an interesting subject, which, however, is outside the scope of these Notes. 1 Proceedings Institut...
- Repeated Loads
- It has already been pointed out that repeated loads do not tend to cause rupture so long as they are kept below the limit of elasticity of the material. Vibration The effect of such loads, or of...
- Extreme Cold
- The effect of extreme cold upon the strength of iron and steel is another open question. It has already been pointed out (see p. 256) that in some castings, the bulkier parts, being the last to coo...
- Forging
- Forging metal consists in raising it to a high temperature and hammering it into any form that may be required. It is not proposed to describe the process, but merely to mention one or two points, ...
- Overheating
- If wrought iron be burnt, i.e. raised to too high a temperature, its tensile strength and ductility are both seriously reduced. These qualities may, however, be to a great extent restored by careful...
- Welding Wrought Iron
- The property of welding possessed by wrought iron is due to its continuing soft and more or less pasty through a considerable range of temperature below its melting point. When at a white heat it i...
- Welding Steel
- The facility with which steel may be welded to steel diminishes as the metal approximates to cast iron with respect to the proportion of carbon; or, what amounts to the same thing, it increases as t...
- Welding Steel To Wrought Iron
- If the melting points of two metals sensibly differ, then the welding point of the one may be near the melting point of the other, and the difference in the degree of plasticity, so to speak, between...
- Corrosion And Preservation Of Cast Ikon Wrought Ikon, And Steel
- Corrosion The different varieties of iron and steel will not oxidise in dry air, or when wholly immersed in fresh water free from air, but they all rust when exposed to the action of water or moist...
- Steel Preservation
- Galvanising consists in covering the iron with a thin coating of zinc. The iron is cleaned by being steeped for some eight hours in water containing about 1 per cent of sulphuric acid, then scoured...
- Painting Wrought Iron
- Before painting wrought iron care must be taken to remove the hard skin of oxide formed upon the surface of the iron during the process of rolling, and which, by the formation of an almost imperceptib...
- Characteristics And Uses Of Iron And Steel
- The student will have perceived that the products of the iron manufacturer may be divided into three classes - cast iron, wrought iron, and steel, the differences in which are caused partly by the amo...
- Copper
- Uses Copper is used by the builder chiefly for slate nails and bell wires, sometimes for rain-water pipes and gutters, for covering roofs, for lightning-conductors, and for dowels; also for bolts a...
- Lead
- Uses Lead is much used by the builder for cisterns, pipes, flat roofs, etc., and from it is prepared white lead, the basis of most ordinary paint. The engineer requires it as a bedding for the ends...
- Action Of Water Upon Lead
- Soft water, especially when full of air, or when containing organic matter, acts upon lead in such a way that some of it is taken up in solution, and the water is poisoned. This makes lead a danger...
- Water Pipes
- The thickness and consequently the weight of lead pipes used for water supply should be regulated by the pressure of water they are intended to bear. 1 Parkes' Hygiene. The following Table shows...
- Water Pipes. Continued
- Coating Lead Pipes To Prevent Poisoning Several methods have been proposed for coating and lining the insides of lead pipes to prevent the water conveyed by them from being poisoned. All of thes...
- Lead Encased Pipes
- Tin pipes, and copper pipes, lined with tin, have been proposed as substitutes for lead pipes, but they are too expensive. The lead encased pipe, made under Haines's patent, has, however, been foun...
- Lead Encased Pipes. Continued
- Strength Of Lead Pipes And Lead-Encased Pipes Mr. Kirkaldy found the strength of lead pipes and of lead-encased pipes to be respectively as follows: - 1 Lead Pipe. Lead-en...
- Zinc
- Uses Zinc is much used for roofs, for light gutters and pipes, for cisterns, chimney pots, ornaments, ventilators, etc.; for slating nails, for tubing, and for covering iron to protect it from oxid...
- Zinc Gauge
- The following Table shows the weight of zinc per square foot for the various numbers of the Zinc Gauge, properly so called. This gauge originated in Belgium, and is sometimes called the Belgian Zinc G...
- Tin
- Uses Tin is used in building for lining lead pipes, occasionally as a protective covering for iron plates, and for small gas tubing. Ores The metal is obtained from an ore called tin-stone ...
- Alloys
- Alloys are mixtures formed by melting two or more metals together. They are not, however, mere mechanical mixtures, for they often exhibit properties different from those possessed by the metals in...
- From Patentee's Circular
- Large castings in bronze are often not homogeneous throughout their mass, in consequence of the difference in fusibility of the copper and tin. Gun Metal also differs in the proportions of its cons...
- Soldering
- It is not proposed here to describe the operations connected with soldering of different kinds, but one or two points may be noticed with advantage.2 The surfaces to be united must be perfectly cle...
- Tin Brazing
- The process of brazing is conducted as follows: - Granulated spelter and borax, ground together in water, are spread over the carefully cleaned surfaces of the joint, and exposed gradually to the h...
- Soft Soldering
- Soft solder is applied in several different ways. For joints in lead the surfaces to be soldered are carefully cleaned and covered with tallow - the space around is smeared with a mixture of size a...
- Fluxes
- The fluxes used are as follows: - For hard soldering - Borax. For soft soldering - (with solders of about 2 tin, 1 lead) - the flux is varied according to the metals to be united, as shown below: -...
- Tables Showing The Properties Of Metals
- Tables showing the properties of metals, and giving the weights of plates, wires, tubes, angles, tees, and sections of various kinds, are to be found in Moles worth's, Hurst's, and other engineering p...
- Contraction Of Metals In Cooling
- Table showing the Contraction of different Metals in Casting. Melting Points of Alloys of Lead and Tin Degrees Fahr. Metal. Contraction. In fractions...
- Gauges
- Imperial Standard Wire Gauge. - The following Table gives the thicknesses of the Standard Wire and Sheet Metal Gauges - sometimes described as the SWG - approved by Her Majesty's order in Council 1st ...
- Gauges. Continued
- Birmingham Plate Gauge Mark or No. Thickness in inches. 1 .004 2 .005 3 .008 ...
- Weight Of Metals
- Weight in lbs. of a Square Foot of Different Metals, in Thicknesses varying by 1/16th of an Inch. Thickness. Inches. Wrought Iron. Cast Iron. Steel. ...
- Chapter V. Timber
- A THOROUGH knowledge of the nature and properties of different kinds of timber is very important to the engineer or architect. Before entering upon a description of the different varieties of timbe...
- Felling
- While the tree is growing the heartwood is the strongest, but after the growth has stopped the heart is the first part to decay. It is important, therefore, that the tree should be felled at the right...
- Characteristics Of Good Timber
- The quality of timber depends greatly upon the treatment the tree has received, the time of felling, and, above all, on the nature of the soil in which it has grown. These branches of the subject d...
- Defects In Timber
- There are several defects in timber caused by the nature of the soil upon which the tree was grown, and by the vicissitudes to which it has been subjected while growing. Heartshakes are splits or c...
- Classification Of Timber
- The following classification of timber is a modification by-Professor Rankine and Mr. Hurst of that originally proposed by Tredgold: - Class I. - Pine Wood (natural order Coniferoe). ...
- Classification Of Fir Timber
- The different trees included under the general head of Fir Timber are divided by botanists into the pines and firs, which produce timber of very different quality, and are distinguished in the growi...
- Market Forms Of Timber
- Before proceeding further, it will be well to describe the different forms to which timber is converted for the market. A Log is a trunk of a tree with the branches lopped off. A Balk is obtaine...
- Descriptions Of Different Kinds Of Timber. Pine Wood Or Soft Wood. Northern Pine (Pinus Sylvestris)
- This timber, frequently known as red or yellow fir, is from the Scotch fir tree. The term Northern Pine has been introduced by Mr. Hurst for the reasons given in the following remarks, extract...
- Timber Varieties In General Use
- Balk Timber The best balks of northern pine are imported from Dantzic, Memel, Riga. Dantzic Timber is grown chiefly in Prussia, and takes its name from the port where it is shipped. Appearanc...
- Planks, Deals, And Battens
- Planks, deals, and battens from the Baltic, when cut from the northern pine (Pinus sylvestris) are known as yellow deal or red deal. When cut from the spruce (Abies) (see pp. 363 and 371), they are ca...
- Prussian
- Memel, Dantzic, and Stettin. - The deals imported are very durable and adapted for external work, but they are chiefly used for shipbuilding. The export of deal from the Prussian ports of Dantzic, ...
- Russian
- Petersburg, Onega, Archangel, Narva. - These are the best deals imported for building purposes. They are very free from sap, knots, shakes, or other imperfections; of a clean grain, and hard well-wear...
- Norwegian
- Christiania, Dram. - Yellow deals (as well as white, see p. 367) and battens are imported from Christiania, together with battens from Dram. They used to bear a high character, being clean and careful...
- Swedish
- Gefle, Stockholm, Holmmnd, Soderham, Gotteriburg, Hernosand, Sundswall. - The greater portion of the Swedish timber is coarse and bad, but some of the very best Baltic deal, both yellow and white, c...
- American Pine
- There are three or four descriptions of this timber in the market, which will now be described. As a rule American pine is in many respects inferior to that from the Baltic. It is generally weaker,...
- American Yellow Pine. Pinus strobus
- American Yellow Pine (Pinus strobus) is produced from a straight and lofty tree found in North America; used to be sometimes known as Weymouth Pine, because it was first introduced into this country...
- Pitch Pine (Pinus rigida)
- Pitch Pine (Pinus rigida) has its leaves in threes, scales of cones rigid, sharp edges, rough bark. The best of this timber comes from the southern states of North America, chiefly from the ports o...
- White Fir Or Spruce (Abies Excelsa)
- This timber is from trees found in Norway, in most of the mountainous parts in the north of Europe, in North America, and also in this country. The peculiarities of the tree, leaves, etc., are give...
- American Spruce
- There are at least four varieties of the tree from which this timber is produced: - The white spruce (Abies alba), which nourishes in the colder parts of North America; the black spruce (Abies nigra),...
- The Larch (Larix Europoea)
- The Larch (Larix Europoea) is found in various parts of Europe; the finest varieties being in Russia. Appearance The wood is honey yellow or brownish white in colour, the hard part of each ring ...
- The Cedar (Cedrus Libani)
- The Cedar (Cedrus Libani) properly so called, comes from Mount Lebanon, and Asia Minor, and is not much known in this country. The wood generally known as cedar is from trees of the genus Juniperus...
- The Kawrie, Cowrie, or Cowdie Pine (Dammara Australis)
- The Kawrie, Cowrie, or Cowdie Pine (Dammara Australis) is found only in New Zealand. Appearance The heartwood is yellowish white, fine and straight in grain, with a silky lustre on surface. C...
- Hard Wood Or Leaf Wood
- The varieties of timber of this class most in use for building purposes are oak, beech, ash, elm, mahogany, teak. These, with a few others, will now be described in more or less detail, according to t...
- American Oak
- There are many varieties of this timber, but that chiefly imported into this country is the White Oak (Quercus alba), so called from the white colour of its bark. It is this variety that is generally ...
- Dantzic Oak
- Dantzic Oak is grown chiefly in Poland, and shipped at the port after which it is named, also at Memel and Stettin. Appearance It is of a dark brown colour, with a close, straight, and compact g...
- Italian Oak - Sardinian Oak
- This timber is formed from several varieties of the oak tree. It is of a brown colour, hard, tough, strong, subject to splits and shakes in seasoning, difficult to work, but free from defects. It is e...
- Beech (Fagus sylvatica)
- Beech (Fagus sylvatica) is known as black, brown, or white beech, all procured from the same species of tree, the difference in the wood being caused by variety in soil and situation. This tree is ...
- Alder (Alnus Glutinosa)
- Alder (Alnus glutinosa) is from a tree found in both Europe and Asia, generally near swamps or the low banks of rivers. Appearance The wood is white when first cut, then becomes deep red on the ...
- Sycamore (Acer Pseudo-Platanus)
- Sycamore (Acer pseudo-platanus) is from a tree generally called the plane tree in the north of England. It is very common in Great Britain, and is found in Germany. Appearance The wood is whit...
- Chestnut (Castanea Vesca)
- This tree flourishes in sandy soils, and is found in most parts of England, in the south of Europe, in Africa, and North America. Appearance The wood resembles that of oak in appearance, but can...
- Ash (Fraxinus Excelsior)
- This tree flourishes throughout Great Britain, in Asia, and America. Appearance The colour of the wood is brownish white, with longitudinal yellow streaks; each annual layer is separated from th...
- Elm (Ulmus)
- No less than five varieties of this tree are found in Great Britain, besides which it flourishes in many parts of Europe and in America. The principal varieties of this timber are as follows: - ...
- The Canada Rock Elm (Ulmus Racemosa)
- The Canada Rock Elm (Ulmus racemosa) is grown in North America, and imported chiefly from Canada. The wood is of a whitish-brown colour, with very close annual rings. It is very tough, flexible, fr...
- Common Acacia (Robinia pseudo-acacia)
- Common Acacia (Robinia pseudo-acacia) is found in America. Appearance The wood is of a greenish-yellow colour, with reddish-brown veins. Its structure is alternately nearly compact and very poro...
- Sabicu (Acacia formosa)
- Sabicu (Acacia formosa), or the true acacia, is found in the West Indies and Cuba. Appearance It resembles mahogany, but is darker, and is generally well figured. 1 Laslett. Characteristic...
- Poplar (Populus)
- Of this tree there are several species common in England. The black and the common white poplar are the most esteemed. The Lombardy poplar is inferior. Appearance The colour of the wood is a yel...
- Mahogany
- Mahogany comes chiefly from Central America as Honduras or Bay mahogany, or from the West Indies as Spanish mahogany. The latter is the best for strength, hardness, and stiffness; the former...
- Jarrah, Australian Mahogany (Eucalyptus marginata)
- Jarrah, or Australian Mahogany (Eucalyptus marginata), comes from West Australia. Appearance The wood is of a red colour, and close, wavy grain, with occasionally figure enough for ornamental pu...
- Teak (Tectona Grandis), Indian Oak
- Teak (Tectona grandis), sometimes called Indian Oak, is found in Southern India, Pegu, Java, Siam, and Burmah. The lightest, cleanest, and most flexible comes from Moulmein; the heaviest and strong...
- Greenheart (Nectandra rodioei)
- Greenheart (Nectandra rodioei) is found in British Guiana and in the N.E. portion of South America. Appearance The section of this timber has a peculiar appearance, being of a fine grain, and ve...
- Mora (Mora Excelsa)
- This timber comes from Guiana and Trinidad. Appearance The wood is of a chestnut-brown colour, sometimes beautifully figured. Characteristics The timber is very tough, hard, and heavy; the...
- Hornbeam (Carpimis betula)
- Hornbeam (Carpimis betula) is from a British tree. Appearance The wood is white and close. The medullary rays are plainly marked, and there is no sap. Characteristics The timber is hard, t...
- Marks And Brands Upon Timber
- There are several distinguishing marks used by the shippers and importers of timber. Some of them refer merely to the number of the balk and to its cubic content, others refer to the quality. In ge...
- Marks And Brands Upon Timber. Continued
- In some cases, when the goods are not branded, the second quality have a red mark across the ends; third being easily distinguished from first quality goods. The well-known Gromoff Petersburg dea...
- Selection Of Timber
- In consequence of the great number of marks used in the timber trade, the difficulty of ascertaining what they mean, and the frequent changes that take place in them, the practical engineer or builder...
- Seasoning Timber
- The object of seasoning timber is either to expel or to dry up the sap remaining in it, which otherwise putrefies and causes decay. One effect of seasoning is to reduce the weight of timber, and th...
- Timber Boiling And Steaming
- Boiling water quickens the operation of seasoning, and causes the timber to shrink less,1 but it is expensive to use, and reduces the strength and elasticity of the timber. The time required varies...
- Decay Of Timber
- To preserve timber from rot or decay it should be kept constantly dry and well ventilated. It should be clear of the influence of damp earth or damp walls, and free from contact with mortar, which has...
- Decay Of Timber. Continued
- Detection Of Dry Rot In the absence of any outward fungus, or other visible sign, the best way is to bore into the timber with a gimlet or augur. A log apparently sound, as far as external appearan...
- Preservation Of Timber
- The best means for preserving timber from decay are to have it thoroughly seasoned and well ventilated. Several processes have, however, been introduced at different times with a view of preventing...
- Preservation Of Timber. Continued
- Combined Process In cases where the complete preservation of the timber is of vital importance, and expense no object, Mr. Britton recommends that the timber should first be injected with metallic ...
- Conversion Of Timber
- In reducing timber from the log or baulk to scantlings, the dimensions and form that the timber ought to possess when actually in use should be borne in mind, in order that proper allowance may be mad...
- Conversion Of Timber. Continued
- Conversion Of Tir At the great saw-mills in Sweden and Norway each log is carefully inspected before it is sawn, to find out how many of the most marketable sizes can be made out of it. Thus if 4-i...
- Destruction Of Timber By Worms And Insects
- Timber both in its growing and converted states is subject to the attacks of worms and insects; when these exist in large numbers they remove so much of the wood as seriously to impair the strength of...
- Timber Protection Against Ants
- Of the ants proper, or those belonging to the order Hymenoptera, there are three species in particular which attack timber, viz. - 1 1. The Black Carpenter Ant (Formica fuliginosa), which prefers h...
- Varieties Of Timber Useful For Different Purposes
- The undermentioned are the best of the ordinary descriptions of timber to use for the purposes named. Piles Oak, beech, elm. Posts Chestnut, acacia, larch. Great Strength In Constructio...
- Strength Of Timber
- The following Table, showing the strength and weight of timber, is gleaned from the records of many experiments, chiefly those given by Hodgkinson, Tredgold, Barlow, Rankine, and Laslett. Some of thes...
- Strength Of Timber. Continued
- Resistance To Shearing On this point also but few experiments have been made. The resistance to shearing in direction of the fibres of the wood is of course much less than that across the fibres...
- Chapter VI. Paints And Varnishes
- PAINTS and Varnishes are used by the engineer and builder for covering the surfaces of wood, iron, and other materials, in order to protect them from the action of the atmosphere, or to improve their ...
- Bases
- White Lead is a carbonate of the metal. The best is produced by the Dutch process, which consists in placing gratings of pure lead in tan, and exposing them to the fumes of acetic acid; by these they ...
- Old White Lead
- White lead improves by keeping. It should not be exposed to the air, or it will turn grey (see p. 407). Old white lead of good quality goes further and lasts better than if it is used when fresh; more...
- Red Lead
- Red Lead is produced by raising massicot (the commercial name for oxide of lead) to a high temperature, short of fusion, during which it absorbs oxygen from the air, and is converted into red lead or ...
- Fixed Oils And Volatile Oils. Vehicles
- Oils are divided into two classes - Fixed oils and volatile oils. Fixed Oils are extracted by pressure from vegetable substances; they are of a fatty nature, do not evaporate on drying, and will be...
- Turpentine Oil," "Spirits of Turpentine, or Turps
- Oil of Turpentine, Spirits of Turpentine, or Turps, is an essential or volatile oil, produced by distilling turpentine tapped from pines or larches. The residuum left after distillation is common ...
- Driers
- Driers are substances added to paint in order to cause the oil to thicken and solidify more rapidly. The action of these substances is not thoroughly understood. Chevreuil has shown that the drying...
- Colouring Pigments
- It is unnecessary to give anything like a complete list of the pigments used to produce the colours and tints used by the house painter and decorator. A few of the most useful may, however, be mention...
- Colouring Pigments. Part 2
- Yellows Chrome Yellows are chromates of lead, produced by mixing dilute solutions of acetate or nitrate of lead and bichromate of potash. This makes a medium tint known as Middle chrome. The add...
- Colouring Pigments. Part 3
- Reds Carmine, made from the cochineal insect, is the most brilliant red pigment known. It is, however, too expensive for ordinary house painting, and is not durable. It is sometimes used for intern...
- Colouring Pigments. Part 4
- Uses Of Pigments The uses for which the pigments above mentioned are suitable may be classified as follows - 4 (a). More or less transparent, and fit for graining and finishing. - Blacks (except...
- Proportions Of Ingredients In Mixed Paints
- The exact proportions of the ingredients to be used in mixing paints vary considerably according to circumstances. The composition of paints should be governed by the nature of the material to be p...
- Lead Paint
- Ordinary white paint is generally composed of white lead, linseed oil, driers, and spirits of turpentine. A coloured lead paint is produced by adding a pigment to the above. In the mixture each ...
- White Lead Paint
- Good paint of this description should be made of pure white lead. If it is to be untinted, care must be taken to exclude any substance which will detract from the brightness of the white, and it must ...
- Zinc Paint
- Zinc Paint, ordinarily so called, is made with oxide of zinc (see p. 409), instead of white lead, as a basis. Characteristics And Uses Zinc white does not combine with oil so readily as white le...
- Coloured Paints
- It has already been mentioned that coloured lead paints are produced by adding a suitable pigment to a white lead paint until the required tint is obtained. It would of course be impossible to give...
- Special Paints
- During the last few years a great many substances have been proposed as bases for paint instead of white lead. The paints made with these substances are called by special names, and often have pecu...
- Oxide Of Iron Paints
- In these oxide of iron (see p. 409) forms the basis. They are free from injurious ingredients such as those of lead paints. For painting iron work they are said to be particularly suitable, on the gro...
- Tar Paint
- The paint successfully used for the canvas roof over the tubes of the Britannia Bridge was composed as follows: - Coal tar, 9 gallons; slaked lime, 13 lbs.; turpentine or naphtha, 2 or 3 quarts - the ...
- Coating Floors
- For asphalte floors the composition is made and applied as follows: - 4 parts (by weight) of Venetian red and 1 part of red lead are mixed into a stiff paste with Stockholm tar and well worked togethe...
- Coating Iron
- (1.) The surface of the iron is prepared and coated with two coats of red lead or oxide of iron paint. (2.) An adhesive composition composed of the ingredients mentioned below is then applied rather m...
- Varnish
- Varnish is a solution of resin in either oil, turpentine, or alcohol. The oil dries and the other two solvents evaporate, in either case leaving a solid transparent film of resin over the surface v...
- Ingredients Of Varnish
- The Gums are exudations from trees. At first they are generally mixed with some essential oil. They are then soft and viscous, and are known as Balsams; the oil evaporates and leaves the Resin, which ...
- Resins
- The quality of the resin greatly influences that of the varnish. The softer varieties dissolve more readily than the others, but are not so hard, tough, or durable. Common Rosin or Colophony is eit...
- Solvents
- These must be suited to the description of gum they are to dissolve. Boiling Linseed Oil (and sometimes other oils, such as rosemary) is used to dissolve amber, gum anime, or copal. Turpentine f...
- Different Kinds Of Varnish
- Varnishes are classified as oil varnish, turpentine varnish, spirit varnish, or water varnish, according to the solvent used. They are generally called by the name of the gum dissolved in them. Oil...
- Mixing Oil Varnishes
- The gum must first be melted alone till it is quite fluid, and then the clarified oil is poured in very slowly. The mixture must be kept over a strong fire until a drop pinched between the finger and ...
- Mixing Turpentine Varnishes
- In many cases the resin, such as mastic, dammar, or common resin, is simply mixed with turpentine alone, cold or with slight heat. Care must in such cases be taken to exclude all oil. Application o...
- Recipes For Varnishes
- The following recipes give the proportions of ingredients for a few varnishes in connection with house-painting: - Oil Varnishes Copal Varnishes. - Best Body Copal Varnish? - Fuse 8 lbs. of fine...
- Recipes For Varnishes. Part 2
- Spirit Varnishes Cheap Oak Varnish. - Dissolve 3 1/2 lbs. of clear good resin in 1 gallon of oil of turpentine. Darken, if required, by adding well-ground umber or fine lampblack.8 Oak varnish i...
- Recipes For Varnishes. Part 3
- Water Varnish Light Coloured. - Mix 16 oz. ordinary water of ammonia with 7 pints water, 2 oz. pale (or white) shellac, and 4 oz. gum arabic. Ordinary Mix 6 oz. borax, 2 lb. shellac, and 4 oz...
- Wash For Removing Paint
- Dissolve 2 oz. soft soap, 4 oz. potash, in boiling water, add 1/2 lb. quicklime. Apply hot, and leave for twelve to twenty-four hours. This will enable the old paint to be washed off with hot water. ...
- Chapter VII. Glass
- General Remarks Glass of the kind used in buildings is a mixture of pure sand, soda, and chalk, with a proportion of broken glass,1 etc. These are melted together at a very high temperature, and br...
- Glass Thicknesses
- There are two thicknesses - The usual, about 1/20th inch thick, and weighing some 10 oz. per square foot; and the extra, about 1/15th inch thick, and weighing some 16 oz. per square foot. The Qu...
- Glass Qualities
- The qualities of sheet glass are as follows, and may be used for the purposes mentioned: - A. For pictures (the best). B. Do. (ordinary). Best. For the best glazing in first-class dwelling-ho...
- Sheet Glass Characteristics
- Sheet glass has a somewhat duller surface than crown glass, but can be made thicker and to yield larger panes. Cylinder Glass, German Plate Glass, and British Sheet Glass, are various names given t...
- British Plate Glass
- British Plate Glass, ordinarily known as Plate Glass, is made by pouring white-hot glass on to an iron table, and rolling it out under a heavy metal roller. The surface is either left rough, or pol...
- Fluted Glass
- Small, with about 11 flutes to the inch. Large, with about 4 flutes to the inch. Sizes Those kept in stock range as high as 30 feet in area, the length not exceeding 120 inches, or the width 36 ...
- British Polished Plate Glass
- British Polished Plate Glass is made from material of a superior description, cast and rolled in the same way as rough plate, and then carefully ground down to a plane surface, and polished on both si...
- Interception Of Light By Glass
- The effect of different descriptions of glass on the diminution of light has been shown by experiment1 to be as follows: - British polished plate 1/4 inch thick intercepts 13 per cent o...
- Chapter VIII. Paperhanging
- WALL papers may be divided into three classes: - Common or Pulp Papers, in which the ground is the natural colour of the paper as first made, the pattern being printed upon it. Satin Papers, of whi...
- Paperhanging. Part 2
- English Papers In these each piece is generally 12 yards long and 21 inches wide. It therefore contains 7 square yards. After the margins are removed the paper is 20 inches wide. Each yard in...
- Paperhanging. Part 3
- Varnishing And Painting Wall Papers Wall papers (except the most delicate) may be finished with good copal varnish over two coats of size, or they may be bought ready varnished. Flock papers may...
- Chapter IX. Miscellaneous
- THIS Chapter will include the description of a few materials which could not be conveniently brought under any of the heads comprised in the former chapters. ...
- Glue
- Glue is prepared from waste pieces of skins, horns, hoofs, and other animal offal. These are steeped, washed, boiled, strained, melted, reboiled, and cast into square cakes, which are then dried. ...
- Glue. Continued
- Glues To Resist Moisture A good glue for outside work is sometimes made by grinding as much white lead with linseed oil as will just make the liquid of a whitish colour and strong, but not too th...
- Knotting
- Knotting is the material used by painters to cover over the surfaces of knots in wood before painting. The object is to prevent the exudation of turpentine, etc., from the knots, or, on the other h...
- Paste
- Paste is required by the paperhanger, in different degrees of strength, according to the thickness and weight of the paper to be hung with it. Paste should be made with the best white wheat flour. ...
- Gold Leaf
- Gold leaf is required for gilding, in order to ornament different parts of buildings, more especially the internal fittings, such as the mouldings of the joinery or the decorations of the ceilings or ...
- Putty
- Painters' and Glaziers' Putty is made with whiting (see p. 254) and oil. The whiting is reduced to very fine powder, carefully dried, passed through a fine sieve (about 45 meshes to the inch), mixed w...
- Rust Cement
- Rust Cement, known also as Cast Iron Cement, and by other names, is used for caulking the joints of cast iron tanks, pipes, etc It is composed of cast iron turnings, pounded so that they will pass ...
- Laths
- The laths principally required by the builder are of two kinds - those used for plastering, and those used for roofs to support the covering of slates or tiles. Plasterers' Laths are thin strips of...
- Vulcanised Indiarubber
- Vulcanised Indiarubber consists of indiarubber mixed with 44 per cent oxide of zinc and 4 per cent of sulphur. An excess of sulphur injures the material, causing it to become brittle with age. This...
- Tar
- Coal Tar is produced by heating coal in close iron vessels, and is a bye product in the manufacture of gas. When itself distilled it produces, in various stages - first, coal naphtha, which is useful ...
- Creosote
- Creosote is a product obtained in distilling tar. It is an oily, dark liquid, varying in composition according to the quality of the coal from which it is obtained, and containing hydrocarbons of diff...
- Felt
- Felt, generally saturated with bitumen and other substances, is sold in various forms useful to the engineer and builder. The following information regarding the different descriptions is from the cir...
- Asbestos
- Asbestos, the well-known fireproof and acidproof fibrous mineral, is the basis of several substances useful to the builder.1 The raw material comes from Italy, Canada, California, Australia, etc. T...
- Willesden Fabrics
- Willesden Fabrics 1 are vegetable substances which have been treated with certain compounds of copper and ammonia, the effect of which is to coat and impregnate them with cupro-cellulose, a varnish-li...
- Nails
- There are some 300 varieties of nails, named chiefly from the shape of their heads and points, or according to the particular use for which they are intended. No attempt will be made to describe th...
- Varieties Of Nails In Common Use
- The following descriptions are of nails in common use: - Rose Nails are either wrought, cut, or pressed. They take their distinctive name from the shape of their heads, and are divided into classes...
- Miscellaneous Nails
- Besides the above-mentioned there is an innumerable variety of patent nails of different descriptions and in different metals, also brass-headed and fancy-headed nails, and nails used for special purp...
- Adhesive Force Of Nails
- The following abstract of records of experiments on the holding power of nails may be useful: - Holding Power of Wrought Iron Tenpenny Nails, 77 to the lb., about 3 inches long, nailed through a 1-...
- Adhesive Force Of Nails. Continued
- Screws are made in several other forms besides those mentioned, for special purposes, which need not be further referred to. Screws for Metal are made in different forms from wood screws; the diame...
- Whitworth's Standard Thread
- Screws for bolts and nuts, and for metal work, are now generally made according to Sir J. Whit-worth's standard, the same form of thread being used throughout, and the same pitch and depth of thread b...
- Whitworitis Gas Threads
- For the screwed ends of wrought-iron gas-tubing and for common metal work a shallower thread is used, as shown in the following Table: - Diameter in inches 1/8 1/4...
- Adhesive Power Of Screws
- Mr. Bevan experimented on iron wood-screws 2 inches long, 22/100 diameter at exterior of threads, threads 35/1000 deep, 12 to the inch. These were driven into boards 4 inch thick. The force required t...
- Appendix. Short Note On The Physical Properties Of Materials, And On The Loads And Stresses To Which They Are Subjected
- A DETAILED description of the physical properties of materials, and of the loads and stresses to which they are subjected, would be beyond the province of this volume, especially as the subject will b...
- Material Stress and Strain
- Stress and Strain are words often used indifferently, either to mean the alterations of figure produced in a body by any forces, or to mean the forces producing those alterations. Of late years, ho...
- Material Tenacity, Tensile Strength
- Tenacity or tensile strength is the resistance offered by material to tension, that is to a stress tending to tear it asunder, as, for example, in the case of a vertical rod having a weight suspended ...
| |
|
 |
|
|
|
