American Library Edition Of Workshop Receipts Vol3| by Ernest Spon
Devoted Mainly to Electrical and Metallurgical Subjects
- Preface. Vol 3
- Self-help seems to be the guiding spirit of the present age, and amateur workmen are multiplying on all sides. With this development of popular taste comes a growing demand for handy practical books, ...
- Alloys
- Alloys are compounds of two or more metals. Every alloy may be regarded as a new metal, since it generally possesses properties different from those of the metals of which it is composed; bat as the p...
- Alloys. Part 2
- When three metals have to be united together, they should first be melted in pairs, and afterwards together. Guettier gives the following suggestions on the subject of fusing the metals :--(l) The me...
- Alloys. Part 3
- Fusibility In forming alloys of metals, they do not combine with each other in their solid state (with the exception of mercury), owing to their chemical affinity being counteracted by the force of c...
- Furnaces For Melting Alloys
- Furnaces for melting alloys may be built of common brick and lined with fire-brick; but the best are made with a boiler-plate caisson, 20 to 30 in. diam. and 30 to 40 in. high, usually set down in a p...
- Cruciles
- All the metals and alloys, with the exception of iron and the very fusible metals, are melted in crucibles, of which there are several different kinds. The principal ones in use are the Hessian pots, ...
- Casting
- When brass is ready to be poured, the zinc on the surface begins to waste with a lambent flame. When this condition is observed, the large cokes are first removed from the mouth of the pot, and a long...
- Amalgams
- Mercury unites with a large number of metals, forming definite chemical compounds called amalgams. Some of these are solid, while others exist in a fluid state. It is probable, however, that fluid a...
- Bell-Metal
- An alloy of copper and tin in proportions varying from 3 to 5 parts of copper to 1 of tin. It is of a yellowish-grey colour, hard, brittle, and sonorous, and exhibits a fine-grained fracture. Cooled s...
- Brass
- Brass is perhaps the most useful and important alloy known. Its composition varies widely with the uses for which it is intended, but its constituents are copper and zinc, usually in the proportions o...
- Brass. Continued
- For frosting small brass-work, fasten a circular scratch-brush, made of very fine brass wire, on the lathe, and having previously scoured the brass with strong pearlash lye, hold the work against the ...
- Bronze
- This alloy has been known and employed since very remote ages. It was used exclusively by the ancients for making swords and other sharp instruments, for coinage, statues, and many other useful and or...
- Making Figures
- It is a singular fact that melted gold, silver, copper, and iron, if poured hot into a mould, will take an impression of all the details of the pattern from which the mould was made, only if the mould...
- Fusible Alloys
- Several alloys having very low melting-points are used in the manufacture of children's toys, and for other purposes where great softness is required. They are chiefly as follows:-(1) 8 parts bismuth,...
- German Silver
- This alloy is much used as a substitute for silver; it is composed of copper, zinc, and nickel. The proportions of the three metals are various. When intended as a substitute for silver, they are 50 p...
- Gun-Metal
- This is also an alloy of copper and tin, in the proportions of 8 or 9 parts of the former to 1 of the latter. It is a very tenacious metal, easily forged, and possesses a considerable amount of resist...
- Iron Alloys
- All substances added to iron,.according to Kirk, make it more fusible. Lead added in small quantity makes iron soft and tough, but in excess renders it extreme coldshort. Copper induces extreme re...
- Iron Alloys. Continued
- The iron became very brittle at all temperatures. Karsten found that by the addition of 15 per cent. of fine silver to iron during the refinery operation, the quality of the iron was sensibly deterio...
- Jewellers' Alloys
- The following are summarized from Fesquet :- Algiers metal: (a) 90 tin, 10 antimony; (6) 94.5 tin, 5 copper, 0*5 antimony, a is used for spoons and forks, b for small hand-bells. Argentin: 85.5 tin,...
- Manganese Alloys
- Mangane-sian iron is mixed with copper, melted in a reverberatory furnace, and run into pigs. An alloy capable of being rolled is made by melting this together with zinc and copper. For a bronze capab...
- Manganese Alloys. Part 2
- In making castings, dry sand or loam moulds well coated with charcoal blacking are preferable to green sand moulds; the metal should be well skimmed before pouring, and it should be cast at as low a h...
- Manganese Alloys. Part 3
- Of far greater importance are the manganese tin and zinc bronzes, which were perhaps among the first upon which experiments were made on a large scale. They were obtained by adding to an alloy of c...
- Muntz's Metal
- An alloy of copper and zinc For rolling into sheets, the best proportions are 60 parts copper to 40 zinc; but for other purposes its composition is variable. It was patented in 1832 by Muntz of Birmin...
- Pewter
- Pewter is an alloy of lead and tin, containing sometimes copper, zinc, or antimony. There are three distinct kinds of English-made pewter, viz. (1) Plate pewter, used for dishes and plates, an alloy u...
- Phosphor Alloys
- For the preparation of phosphorus compounds of metals, for example, phosphor-copper, Dr. Schwarz gives the following directions:-A mixture of bone-ash, silica, and carbon is placed in a crucible, and ...
- Solders
- Alloys employed for joining metals together are termed solders, and they are commonly divided into two classes: hard and soft solders. The former fuse only at a red heat, but soft solders fuse at co...
- Specular Alloys
- These are employed fur making metallic reflectors, requiring a true white colour, good lustre, and a hard, clean surface not easily tarnished or scratched. Fesquet gives a number of combinations, as f...
- Tungsten Bronzes
- In the arts, tungsten bronzes of different colours are used, namely, golden-yellow, reddish-yellow, purple-red, and blue. The first two crystallize in forms resembling cubes, while the third is obtain...
- Type-Metal
- This alloy, used for printers' type, is often composed of 6 parts lead, and 2 antimony. It is of a blackish-grey colour, and is softer than tin and copper, but a little harder than lead. Several of th...
- Miscellaneous Alloys
- The following is a table of the proportions of the various metals in the alloys most commonly employed in the arts and manufactures. The term parts means parts by weight. The abbreviations are: Cu, ...
- Miscellaneous Alloys. Part 2
- The name of kara-have is given to a sort of bell-metal, consisting of copper, zinc, tin, and lead, and having some resemblance to alloys c and d. Maumene furnishes analyses of Japanese bronzes sent h...
- Miscellaneous Alloys. Part 3
- Pieces of this very difficult sort of workmanship are produced by overlaying and soldering together a certain number of plates of the said metals or alloys, by hammering, kneading, resoldering, fillin...
- Miscellaneous Alloys. Part 4
- White Alloy This compound can be turned, filed, and bored; does not adhere to the mould, and will retain its polish a long time after exposure to the air. Contains 10 cast-iron, 10 copper, 80 zinc. ...
- Anti-Friction Alloys
- When the so-called anti-friction alloys, or white metals, were introduced, reports as to their value soon made their appearance, and one of the most important was that of Nozo, the engineer of t...
- Bismuth Bronze
- A new metallic alloy, which the inventor calls bismuth bronze, has been recently introduced by James Webster, of Solihull, as specially suitable for use in sea-water, for telegraph and music wires, an...
- Aluminium
- This metal possesses properties which render it one of the most useful yet discovered, and the only bar to its greater employment has hitherto been its high price. There is an immediate prospect of th...
- Antimony
- Metallic antimony rarely occurs native and as an ingredient in the sulphides of other metals. Its chief commercial source is antimony sulphide (grey antimony), containing 74 Per cent. antimony and 26 ...
- Barium
- The principal ores of barium are the sulphate or heavy spar (BaS04), and the carbonate or witherite (BaCO3,). Metallic barium may be prepared from the monoxide baryta, from the chloride, and from othe...
- Beryllium Or Glucinum
- This metal occurs in many minerals, especially the varions forms of beryl, including the gems emerald and aquamarine. Wohler first obtained it as a dark-grey powder by fusing the chloride with potassi...
- Bismuth
- This metal occurs In many minerals, but not in such quantity as to make its extraction profitable. It is almost exclusively obtained from cobalt speiss at the Saxon smelt-works, the residue containing...
- Cadmium
- This metal occurs in calamine and zinc blende in proportions varying from 1 1/2 to 3 per cent. It is recovered during the smelting of these ores for their metallic zinc in the following manner:-The mo...
- Caesium
- This rare metal is met with in small quantities in the ores of other alkali metals (notably lithium), and in some mineral waters. On passing an electric current through melted caesium chloride, little...
- Calcium
- Calcium minerals occur throughout the world in the greatest profusion, the most familiar examples being the various forms of carbonate (chalk, coral, limestone, marble, and magnesium limestone or dolo...
- Cerium
- This rare metal occurs in a few uncommon minerals, in the following approximate proportions, calculated as 6xide (Ce2O2):-61 Per cent. in cerite, 12 1/2 in orthite, 8 1/2 in wohlerite, and 2f in gadol...
- Chromium
- This somewhat rare metal occurs chiefly in native lead chromate or crocoisite (PbCrO4), and in chrome-iron ore or chromite (FeO.Cr203), the. latter of which is mainly used for the preparation of chrom...
- Cobalt
- This metal occurs sparsely in some arsenical ores, usually accompanied by nickel; its chief sources are cobalt speiss ([CoNiFe] As,), cobalt glance ([CoFe] [AsS],2 ) and cobalt bloom ( [Co2(As04)2 + 8...
- Copper
- Properties Copper is a light, hard metal, very liable to rust; all salts, unctuous bodies, and many other natural substances are solvents of it. It is remarkably sonorous, being the basis of all allo...
- Copper. Part 2
- Jigging The first of these operations is technically known as jigging the ore in a cistern of water. Formerly this was universally done by filling a quantity of ore into a copper-bottomed sieve, an...
- Copper. Part 3
- Mention must be made of the ore rejected as too small by spatters and cobbers; it is picked over, and the richest pieces are passed to the best-ore heap. The remainder is subjected to a riddle with 1-...
- Copper. Part 4
- 9. Preparation of crude copper by roasting and fusion of regulus. 10. Refining and toughening of crude copper, producing fine metal. For the purpose of showing clearly the character and objects of t...
- Copper. Part 5
- The ore and flux having been introduced through the hopper, the workman rapidly spreads the charge over the bod b of the furnace, and then introduces the scoria, evenly distributing it over the surfac...
- Copper. Part 6
- Fourth Operation The furnace is of the same form as that employed in the second operation, excepting that there is no basin-formed recess in the bed, but a gradual slope of it, so as to discharge the...
- Copper. Part 7
- The Eighth Operation is conducted in a furnace precisely similar in every respect to that employed for the seventh. The materials, constituting the charge are white metal, produced from the sixth and ...
- Copper. Part 8
- If the poling has not been continued long enough, the metal will be brittle, as also if the poling has been continued too long. In the latter case, the metal is restored, but with some difficulty, by ...
- Copper. Part 9
- Fig.11 The crude matte is routed 5 times in stalls containing 8 to 10 tons; each firing lasts 2 hours, and consumes about 14 bushels of charcoal and 1/4 ton of wood. The smelting for black copper ...
- Copper. Part 10
- Trials made at the Mansfield Copper Works have proved that an addition of 0*45 per cent. of manganese-copper is sufficient to toughen copper, which only retains 0.005 to 0.022 per cent., while the gre...
- Copper. Part 11
- Welding The great obstacle heretofore experienced in welding copper has been that the oxide formed is not fusible. If any fusible compound of this oxide could be found, it would render such a weld po...
- Didymium
- This rare metal occurs in small proportions in a few uncommon minerals, notably in gadolinite, which contains about 8 1/3 per cent. of the oxide, and in cerite (less than 4 per cent.) It is extremely ...
- Electrics. Alarms. House Electric Alarm
- This article is designed to convey a number of practical hints connected with the various branches of applied electricity, such as cannot be found in any existing treatise. Attention will be confined ...
- Tell Tales For Cisterns
- (1) In Fig. 14, a is the tank, b the float, c V-wheels, d light wire rope, e counterbalancing weight (which must be adjusted so as not to prevent the float b falling with the water), f eye (through wh...
- Time-Signals
- (1) To ring at 6 o'clock. Fig. 23 shows a small clock a, with which to work the bell; b, battery consisting of two Leclanche cells; c, a disc, with a notch cut in it, running out to the diameter of th...
- Tell-Tale Clock
- A drum d (Fig. 28) carries a strip of paper wound upon it. The surface has grooves cut in it, either circular or (if to indicate for more than 12 hours without attention) spiral. In the latter case, o...
- Galvanic Battery
- A galvanic battery consists of 2 electrical conducting bodies placed in a fluid which will exert greater chemical action on the one (the positive element) than on the other (the negative element)...
- Bichromate Batteries
- Bichromate batteries of bottle shape as in Fig. 29, with 2 carbon plates, a sliding rod and movable zinc plate, are very extensively used by experimenters and lecturers, because they are always ready ...
- Bichromate Batteries. Continued
- The h.p.-hour is 1,980,000 foot-pounds, and as that was practically-obtained with the consumption stated, an estimate of the cost can be easily calculated. Hospitaller states that 5 batteries, of 6 ce...
- Bunsen's Zinc-Carbon Battery
- Bunsen's zinc-carbon battery is a modification of Grove's, the only difference from the latter being the substitution of carbon for platinum foil. The carbon rod or plate becomes brittle in time throu...
- Callan's or May-nooth Battery
- In the Callan's or May-nooth battery, a cast-iron vessel is used as the containing cell, and forms the negative element. A zinc plate, constituting the positive element, is placed in a porous cell wit...
- Copper Oxide Battery
- Lalande and Chaperon have introduced a new battery with a single liquid and a solid depolarizing element, by associating copper oxide, caustic potash, and zinc. This battery possesses remarkable prope...
- Cruikshank's Battery
- This battery consists of zinc and copper plates united in pairs, and fitting into grooves in a wooden trough, the space left between the pairs of plates accommodating the excitant. This latter is dilu...
- Granule Carbon Battery
- This battery conlists of an outer Teasel a (Fig. 34), containing an inner porous cell b; in the outer vessel is a. carbon plate c, packed round with broken gas retort carbon; the zinc rod d is...
- Insulite Battery
- The British Insulite Co. have brought out a sealed cell suitable for domestic use, as shown in Fig. 37. It is an oblong vessel on plan, with a diaphragm of porous material securely cemented to opposit...
- Leclanche Battery
- This form of battery, Fig. 38, is in very general use for electric bells, its great recommendation being that, once charged, it retains its power without attention for several years. 2 jars are employ...
- Lime Chromate Battery
- This is a double-liquid battery devised by Fitzgerald and Molloy; it is said to be as constant as the Bunsen, almost as effective, and much cheaper. The chief point is to secure a large negative surfa...
- Smee's Battery
- This form of battery is very extensively used, and consists of a platinized silver plate for the negative element, with zinc plates for the positive, as in Fig. 39. The platinized silver plate is usua...
- Thermo-Electric Battery
- When the junction, of 2 different metals is heated, an electric current is generated, the greatest effect being obtained with antimony and bismuth. Such generators are known as thermo-electric piles. ...
- Residues
- From a table compiled by kolb, one of the secretaries in the Imperial Telegraph Department of Germany, it seems that of the 12,350/. spent during the year 1881-82 upon the 127,166 galvanic cells in us...
- Bells
- An ordinary electric bell is merely a vibrating contact-breaker carrying a small hammer on its spring, which hammer strikes a bell placed within its reach as long as the vibration of the spring contin...
- Bells. Continued
- (6) 1 Bell And 2 Press-Buttons The next system is an arrangement of 2 press-buttons in different places to ring the same bell. Having fixed the bell and battery, and decided upon the positions of the...
- Making An Electric Bell
- The following description applies to 3 sizes - viz. for a 2 - in. bell, hereafter called No. 1; 2f - in., or No. 2; 4 - in., or No. 3, which sizes are sufficient for most amateurs' purposes, and, if p...
- Making An Electric Bell. Part 2
- The wires are connected to the push B, and battery C. Thus, when the push B is pressed down, the circuit is closed, the iron core in electro - magnet is magnetised, and pulls the iron armature on b cl...
- Making An Electric Bell. Part 3
- Fig. 51. (9) Method of producing continuous ringing from an ordinary Electric Bell. - The method works well, is inexpensive, and any one with ordinary intelligence could make and fix one for hims...
- Making An Electric Bell. Part 4
- In some instances, the falling of the block might be made to complete a circuit through the magnet coils of a separate bell apparatus, instead of the magnet on the block being made to ring the bell. ...
- Making An Electric Bell. Part 5
- Neatsfoot - oil is the best kind of grease for this purpose, (g) Get new carbons, made out of gas - retort scurfing, as it is called, then prepare the ends that are out of the solution, thus: - Tho...
- Carbons
- The rods first used for the electric light were of wood charcoal, quenched in water or mercury; they burnt with brilliancy and regularity, but too rapidly. Next, the carbon which is deposited in gas -...
- Carbons. Continued
- Alumina silicate and alumina require a very strong current to effect their decomposition, and burn with a blue flame of small illuminating power. Silica melts and volatilizes without undergoing decom...
- Coil Induction
- An electrified wire is capable of exciting a current In another wire placed near it, but nut In contact, and such a current is termed an induced current. Induced currents generally have a very high el...
- Contact - Breakers, Or Interruptors
- Fig. 60 represents the apparatus devised by Dr. Ritchie as a mode of obtaining rotary motion by the temporary magnetization of an iron bar, which is extensively employed as a contact - breaker. It con...
- Coil Intensity
- The parts of an intensity coil are: reel, primary coil, secondary coil, iron bundle or core, contact - breaker, condenser, pedestal or base, and commutator. The dimensions given may be considerably va...
- Contact - Breaker
- The form used for intensity coils is the vibrating contact - breaker. It is not desirable to use a separate electro - magnet for intensity coils, as a resistance is offered by it to the passage of the...
- Commutator
- This is shown in Fig. 64; its use is to change the direction of the currents through - the primary and secondary circuits. It consists of an ivory or ebonite cylinder, 1 in. long and 1 in. diameter. M...
- Coil Resistance
- These consist of coils of wire (German silver or silver - iridium alloy), wound with great care, and of a length to have a resistance of a definite number of ohms. ~ The following instructions for mak...
- Dynamo - Electric Machines
- The following description of dynamo - electric machinery is mainly derived from a series of Cantor Lectures by Prof. Silvanus Thompson, delivered before the Society of Arts in December, 1882. A dynam...
- Field - Magnets
- The coils of the field - magnets cannot be constructed of no resistance; thus they always waste some of the energy of the currents in heat. It has been argued that it cannot be economical to use elect...
- Armature Cores
- (a) Theory dictates that if iron is employed in armatures, it must be slit or laminated, so as to prevent the generation of Foucault currents. Such iron cores should be structurally divided in planes ...
- Commutators, Collectors, And Brushes
- (a) Commutators and collectors, being liable to be heated through imperfect contact, and liable to be corroded by sparking, should be made of very substantial pieces of copper. (b) In the case of a c...
- Methods Of Exciting Field - Magnetism
- There are certain theoretical considerations respecting the method of exciting the magnetism of the field in which the armatures are to revolve. The main methods are 4 in number. Magneto - Dynamos M...
- Organs Of Dynamos As Constructed In Practice
- Field - Magnets In the classification of dynamos, those of the first class required a single approximately uniform field of force, whilst those of the second required a complex field of force differi...
- Organs Of Dynamos As Constructed In Practice. Part 2
- The Weston armature has the drum surface cut up into longitudinal poles; there is a similar armature by Jablochkoff, in which the poles are oblique. Ring armatures are found in many machines, but the...
- Organs Of Dynamos As Constructed In Practice. Part 3
- Fig. 73. It is worth while to mention the peculiarity of form of the Burgin armature, consisting of 8, or, in the newest machines constructed by Crompton, of 10 rings, set side by side. Each ring ...
- Organs Of Dynamos As Constructed In Practice. Part 4
- The brushes, therefore, were not getting their proper difference of potential; and in part of the coils the currents were actually being forced against an opposing electromotire force. In a badly - ar...
- Alternate - Current Dynamos
- By far the most important of the dynamos of this second class are those usually known as alternate - current machines. This type of dynamo was originally created by Wilde, in 1867. The field - magn...
- Alternate - Current Dynamos. Continued
- Dynamos Of Third Class The earliest machine which has any right to be called a dynamo was of this class. Barlow and Sturgeon had shown that a copper disk, placed between the poles of a magnet, rot...
- Measuring Electric Currents
- The following observations on the measurement of electric currents are condensed from J. N. Shool - bred's paper on the . Measurement of Electricity (J1. Soc. Arts,' Ap. 6, 1883), and one by Profess...
- Non-Registering Instruments
- (A) Current Measurers (1) Siemens's Electro - dynamometer consists of a fixed coil, and of a movable coil suspended by a thread and a spiral spring, the normal position of the latter being at right a...
- Registering Instruments
- These may be divided into 2 classes - (a) Quantity or coulomb meters; (6) energy or work meters. (A) Quantity Or Coulomb Meters These are separated into those based upon electrolytic action, and tho...
- Registering Instruments. Continued
- In Lane - Fox's quantity meter the entire current of supply is passed through the coils of a solenoid; the movable core, or plunger (the degree of insertion of which within the solenoid depends upon t...
- Microphones
- The microphone has been so named from its power of increasing sounds resulting from mechanical vibrations transmitted by solid substances, and thus rendering audible such ordinarily inaudible sounds a...
- Microphones. Part 2
- As far as Blyth's experiments go, the following appears to be something like the true explanation of the microphone action. What he has termed the air and the tremor effects take place simultaneously....
- Microphones. Part 3
- Having con nected your batteries and telephones, bring the feet of the magnet within J in. of the iron wire (the wire must not touch the magnet). Now speak, standing 3 or 4 ft. away - your friend will...
- Microphones. Part 4
- Take the carbon pea which you have roughed down in the lathe, put it in the hole in the steel plate, rub it round in every direction between the finger and thumb, and after a while it will pass throug...
- Microphones. Part 5
- Fig. 92. The sound - board is fastened to the inside of the box by a leather hinge glued along the upper edge; and on a slip of wood, the thickness of rubber - ring, a small spring presses at the ...
- Motor Principles and Applications
- This section maybe divided into 2 parts: (l)the principles and practice of the construction of electro - motors, and (2) their application. The first may be best studied from Prof. Thompson's Cantor L...
- Motor Principles and Applications. Part 2
- Now, if a galvanometer is placed in circuit with the electric - motor and the battery, it is found that when the motor is running it is impossible to force so strong a current through the wires as tha...
- Motor Principles and Applications. Part 3
- It can, in fact, work more efficiently if it be not expected to do its work so quickly. Siemens has, in fact, proved that if the motor be arranged so as to do its work at less than the maximum rate, b...
- Motor Principles and Applications. Part 4
- R and the useful work done is - W' = e' (E-e) R That is to say, with no greater loss in heating, more energy is transmitted and more work done. Also the efficiency is greater, for w' /...
- Motor Principles and Applications. Part 5
- It is possible to use as a motor any direct - current dynamo, whether the field - magnets be series - wound, shunt - wound, separately excited, or permanently magnetized. There is this curious point o...
- Motor Principles and Applications. Part 6
- One great advantage of electric motors is, that they can be so easily fixed directly on the spindle of the machine which they are to drive; an advantage not lightly to be thrown away. Application Wh...
- Railways
- The Portrush electric railway extends from Portrush a distance of 6 miles. The line is single, and has a gauge of 3 ft. The gradients are exceedingly heavy, being in parts as steep as 1 in 35. The cur...
- Railways. Continued
- We have then E1 = w/ f . (1) If R be the resistance in circuit by Ohm's law. C= E-E / R = E-w/ f(C); R and therefore w= (E - CR)/f(C) . (2) Let a be the effciency with which ...
- Machinery. Electric engines
- Electric engines may be used with advantage in cases where the importance of utilizing power at a distance from an original motor is sufficient to compensate for the loss in converting the power into ...
- Phonographs
- The phonograph is an instrument by which sounds can be imprinted on soft metal, such as tinfoil, and reproduced with distinctness and accuracy of tone any number of times. It consists of 3 parts: a re...
- Phonographs. Part 2
- Screw - bolts of this description are used for fixing the expanding bodies of ordinary photographic cameras, and may be had of any optician. H and £ are fitted with a similar bolt. Two rather stiff pi...
- Phonographs. Part 3
- Before putting a tinfoil upon the cylinder, the 2 nuts are removed, and the diaphragms turned back out of the way. A little gum brushed along' one end of the tinfoil will be sufficient to keep it firm...
- Photophones
- Fig. 101 illustrates the principle of Bell's photophone, and shows one of the most successful arrangements. A beam of light from any source is concentrated on the diaphragm a by the lens b, and the di...
- Electrical Storage Of Energy
- The following observations on the electrical storage of energy are gathered from Prof. Oliver Lodge's Cantor lecture on Secondary Batteries and the Electrical Storage of Energy. Methods of storing ...
- Electrical Storage Of Energy. Part 2
- The peroxide penetrates deeper and deeper into the plates as they are successively used as positives, and by repeated reversals their surfaces ultimately come to have a porous spongy condition - a sta...
- Electrical Storage Of Energy. Part 3
- Having explained the process of charging and discharging the cells, Dr. Lodge mentions that the reduction of the sulphate is rather troublesome, and it is desirable that no more sulphate should accumu...
- Electrical Storage Of Energy. Part 4
- This is the cistern as opposed to the constant supply system, and it is probable that, as in water services, the latter, by which a central store supplies the force, will be most popular. The central ...
- Electrical Storage Of Energy. Part 5
- Connections must oe provided to the sheets in either form, and the best is - made by strips of lead attached carefully to the sheets by soldering, which should be well protected by good cement; copper...
- Electrical Storage Of Energy. Part 6
- Alkaline solutions cannot be used with lead, because they dissolve it; but they may be employed with some other metals, as iron, which would absorb H at one plate and form peroxide at the other, produ...
- Telephone Construction
- Before describing the construction of various forms of telephone, it is necessary to explain the principles underlying its mode of action. The sensation felt in the organ of hearing, and known as a s...
- Telephone Construction. Part 2
- Secondly, when, to obviate this difficulty, the speaker speaks with his mouth very close to the current - regulator, the moisture of his breath condenses upon the contact points or adjacent parts of t...
- Telephone Construction. Part 3
- Fro. 112 Fig. 113. When the plate of the microphone is in the position shown in Fig. 113, so as to close the box, the wire a, Fig. 115, is joined to the wire a, Fig. 114, and the wire 6, Fig. ...
- Telephone Construction. Part 4
- (c) Fig. 118, making the bell - case act as switch - board, 4b are the line ter - O 2 ininals; a is in connection with one terminal of bell, battery, and telephone respectively; b is connected with...
- Telephone Construction. Part 5
- (B) Telephone Circuits And Call (Fig, 122) When the button r is pressed, the spring h makes contact with support s. A current then flows from battery to c through spring A by means of a wire to b, t...
- Telephone Construction. Part 6
- Fig. 125. To call the distant station, press the button a, which breaks contact at b, and puts the line / and carbon of battery c in contact at d. The circuit is completed by putting the zinc of b...
- Enamels And Glazes
- Enamels and glazes, properly speaking, are opaque, vitreous, coloured materials, tractable in the fire, and used in ornamenting metals and pottery; but it will be convenient to add here a few recipes ...
- Enamels And Glazes. Continued
- The iron doors of such an oven open into the room where the varnishing operations are carried on, so that the atmosphere of this room in which the men work is always more or less charged with irritati...
- Dial - Plates Enamelling
- Dial - plate enamelling includes the manufacture of watch and fine clock dial - plates, with fluted plates for enamel painting, and is divided into 2 branches-hard enamelling, and soft or glass enamel...
- Dial - Plates Enamelling. Part 2
- The rings employed in enamelling are generally made of a mixture of pipe - makers' clay and Stourbridge clay, rolled up In the form of cylinders, and turned in a lathe by means of a cylindrical piece ...
- Dial - Plates Enamelling. Part 3
- The ground silver sand is used to give sharpness to the polishing stones, and wear away the enamel with greater celerity. The act of polishing is continued till all the gloss is ground off the surface...
- Transparent Enamelling
- The operations of transparent enamelling are nearly similar to what has been already described in enamelling dials As the work is generally of a more minute kind, greater delicacy of handling is perha...
- Iron Enamelling
- {1) Enamelling inside of Iron Saucepans. - The article is first cleansed from all oxides by placing it in an acid solution, then dried, after scouring with sand to a grey colour, which shows it to be ...
- Iron Enamelling. Continued
- (7) Mottled Enamel (a) The metal is cleaned in the usual way in an acid bath, then, without employing an alkaline bath, it is, after the usual scouring to remove the scale, placed in clear water and ...
- Photograph Enamelling
- (1) A very good formula for enamelling or encaustic paste is as follows: - Pure virgin wax, 400 parts; gum elemi, 8; benzole, 160; oil of spike, 14. Apply to the surface of the print with a camel's ha...
- Photograph Enamelling. Part 2
- This stage reached, plunge the plate into the bath, without letting the collodion get too much set; if the setting be prolonged, the .result is not so good. A nitrate bath means a solution of 30 gr....
- Photograph Enamelling. Part 3
- To use the enamel toning bath, proceed as follows:- Pour some out into a clean dish to the depth of about 1/2 in., stand near to this a large dish filled to the depth of 1 in. with clean water, and al...
- Photograph Enamelling. Part 4
- A gas muffle furnace is preferable for burning the enamels in, to one heated by coke; whichever is used, it should be ready and at the full heat, a clear cherry - red inclining to white, but by no mea...
- Pottery Glazing
- Glaze is a glass built up of 2 or more silicates. The normal felspathic glaze consists of sodic or potassic and aluminic silicates; salt glaze, of sodic and aluminic silicates; lead glazes are mixture...
- How to Glaze Earthenware
- (1) For the glaze, a mixture of borax, Cornish stone, calcic carbonate, flint, and kaolin, is first fused in a small reverberatory furnace, shown in section in Fig. 127: A is the stoke hole; M, fire -...
- Glazing Porcelain
- (1) The material used for the glaze is a natural mixture of felspar and quartz, and is known as pegmatite. Its average composition is - silica, 74.3; alumina, 18.3; potassic oxide, 6.5; calcic oxid...
- Glazing Wood
- (1) In a clean bottle put 1 oz. crushed gum benzoin, add 1 gill proof spirit, lay by in a warm place, well shake the bottle frequently. This is a superfine finish for mouldings and turned work. May be...
- Erbium
- This metal, like di - dymium, is one of the so - called cerium group, and is met with to the extent of nearly 3 Per cent. (as oxide) in the mineral gadolinite. It has not yet been obtained in the fr...
- Gallium
- This metal occurs in minute proportions in some samples of zinc - blende. To separate it, the blende is dissolved in sulphuric or hydrochloric acid, or in aqua - regia, and the solution is decomposed ...
- Glass
- This article has no pretension to being a general treatise on the manufacture of glass, which would here be out of place, and which is already given in a very complete manner in Spons' 'Encyclopaedia'...
- Glass. Part 2
- The metallic oxides necessary for the production of coloured glass, are introduced into the crucibles with the raw materials. Sheets or circles may be entirely gathered from one crucible, or from more...
- Glass. Part 3
- Imitation Gems The property of glass to display a variety of tints by the addition of metallic oxides, is made use of for the production of artificial gems. The percentage composition of the base use...
- Glass. Part 4
- (2) Small, rough, refuse diamonds, set in the end of a tin tube, make effective drills for glass. (3) Richter and Co., Chemnitz, have a way of impregnating thin German silver discs (15 to 25 mm. diam...
- Enamelling Glass
- An enamel paint may be either an exceedingly fusible glass, covered by some metallic oxide, and rendered opaque by the presence of arsenic trioxide, or an equally fusible transparent glass, mixed with...
- Etching Glass
- (1) Glass is etched by hydrofluoric acid, or by hydrofluoric acid gas. The gaseous acid has the property of producing a surface which resembles ground glass in its appearance; the liquid acid produces...
- Glass Gilding
- (1) Thoroughly clean the glass, then take some very weak isinglass size, and while warm float the glass where you intend the gold to be laid, with the size and a soft brush; then lay the gold on with ...
- Glass Ornamenting
- Some ornamental processes during manufacture are:- (1) Upon the surface of a vessel in course of manufacture, small drops or seals of molten coloured glass may be fixed, and may be pressed by moulds i...
- Glass Ornamenting. Continued
- By mixing various metallic oxides with the boracic acid, designs in colour may be produced. (Dode..) The surface to be ornamented is covered with a sensitive varnish, and the design, being made trans...
- Protecting Glass
- (1) In chemical laboratories it is customary to put a coating of clay on glass vessels that are to be exposed to a temperature that would soften or melt the glass, or where they are liable to be broke...
- Spun Glass
- To make tine glass thread, the glass is brought to a state of fusion, a glass rod is dipped in it, and thus a thread is pulled out, which solidifies first in its thinnest parts, and so causes a unifor...
- Writing On Glass
- (1) Ether, 500 gr.; sandarac, 30 gr.; mastic, 30 gr. Dissolve, then add benzine in small quantities, till the varnish, spread on a piece of glass, gives it the aspect of roughened glass. The varnish i...
- Gold
- Gold is one of the most widely distributed metals, and occurs almost always in the native state under 3 separate conditions - (1) as free gold in ancient and modern alluvial deposits; (2) encased in n...
- Gold. Part 2
- The solution of copper sulphate has now to be dealt with. It is therefore transferred, to a lead - lined tank, heated by a fire beneath, where it is evaporated down, and from which it is transferred i...
- Gold. Part 3
- From the top a wide pipe conducts away fume which rises into it to one of the leaden condensing chambers already described. It is to the advantage of the refiner to save as much as possible of the ni...
- Indium
- This metal occurs in very small proportions in some zinc - blendes. It is best prepared from metallic zinc from Freiberg, Saxony, which contains about 1/10 per cent., in the following manner: - The zi...
- Iridium
- This valuable metal occurs pretty abundantly in platinum and osmium alloys, forming 27 to 77 Per cent. of the mineral platiniridium, and 53 1/2 to 58 Per cent. of osmiridium. The preparation of pure i...
- Iron And Steel
- Without entering into the details of the manufacture of iron and steel, which would be out of place here, there are many matters relating to the subsequent modifications and applications of these meta...
- Malleable Iron
- Malleable iron is iron which has been decarburized (deprived of its carbon) by the action of air upon it in a molten state. There are several ways of doing this. (a) The bloomery process, necessi...
- Malleable Iron. Continued
- It can be worked and polished with file and chisel, or forged and welded at a moderate red heat. (E) Malleable - Iron Castings The term malleable - iron castings means an iron that has been cast int...
- Melting Iron
- There is probably as much reason for changes in the plan of melting iron as in moulding jobbing work. Melters will sometimes get nervous at being ordered to charge up their cupola in as many different...
- Iron Tempering
- This term is here employed in its widest sense, embracing hardening, case - hardening, softening, toughening, and annealing. It will be convenient first to discuss the principles advanced by different...
- Iron Tempering. Part 2
- It further appears that the rapidity of the first cooling, from the 1112 to 1292 F. (600 to 700 C), to which steel has commonly been heated, to 572 to 752 F. (300 to...
- Iron Tempering. Part 3
- For attaining this end is sometimes used a less powerful hardening fluid, and sometimes a warm instead of a cold fluid, and sometimes the piece is held only a short time in the hardening fluid, and is...
- Iron Tempering. Part 4
- The diminution of the tensile strength by a too strong hardening of a highly carbonaceous steel is, however,' much more rapid than the corresponding decrease in consequence of the content of carbon be...
- Influence Of Carbon in Soft, Tempered, And Hardened Steels
- Prof. Chandler Roberts has shown that in soft, tempered, and hardened steels respectively, the carbon present has distinct modes of existence, as is indicated by the widely different action of solvent...
- Tempering Steel. Influence Of Temperature
- Perhaps the best method ever discovered for tempering steel, resulting in hardness, toughness, and elasticity combined, is that followed in hardening the blades of the famous Damascus swords. The furn...
- Classifying Steels
- The steel of which all cutting tools are made depends more, for its real value, upon the degree of its temper than on the quality of the steel itself. A piece of untempered steel, even the finest grad...
- Testing Steels
- Prof. Kich, of Prague, after several experiments with nitric, sulphuric, and hydrochloric acids, and their combinations, with mordants composed of the salts of copper, etc, has arrived at the conclusi...
- Steel Hardening And Tempering Defined
- It is manifestly desirable to obtain any required degree of hardness by a single process, if possible; hence by heating a known quality of steel to a definite temperature, and quenching it in water or...
- Steel Heat Tests
- This matter would be considerably simplified if, instead of the colour, the degrees of temperature were specified; thus tempered to 460 F. (238 C.) would mean the same degree of hardness as ...
- Beating Steel
- In heating steel to harden it, there arise many considerations, the principal of which are as follows:- As the steel becomes heated, it expands; if one part becomes hotter than another, it expands mo...
- Fuel For Heating
- To prevent de-carbonization for ordinary work, charcoal instead of coal is sometimes used; and where hardening is not done continuously, it is a good practice, because a few pieces of charcoal can be ...
- Steel Cooling and Quenching
- We now come to the cooling or quenching, which requires as much skill as the heating, to prevent warping and cracking, and to straighten the article as much as possible during the cooling process. The...
- Degrees Of Steel Temper
- The considerations which determine the most desirable degree of hardness or temper are whether resistance to abrasion, capability of sustaining great pressure upon a fine edge, or elasticity, is the q...
- Steel Cracking And Splitting
- One of the most serious losses common to our tool and implement manufactories is that of the cracking and splitting of steel during the hardening process. Not only is the article or piece lost after h...
- Modifications Of Steel Dipping
- When a piece of work will be improved by having its exterior hardened and tempered, with the interior left softer, it may be heated in melted lead, the latter being covered with charcoal to prevent it...
- Annealing Steel
- There are many ways of annealing steel: e. heating it to redness in the open or hollow fire, and then burying it in lime, in sand, in cast - iron borings, in dry sawdust, and by packing in carbon in a...
- Steel Recipes
- The following recipes for hardening, softening, tempering, and annealing are classified as nearly as possible according to the character of the article operated upon. Case - Hardening Wrought - Iron ...
- Steel Cutters
- (1) If for a cold set, have it very stiff; round the corners slightly. The principle in tempering cutting - tools for striking on, is to avoid the hard line: the temper should die away gradually. Th...
- Files
- (1) The point of a file, being thinner than the middle, is liable to become hot sooner, and attain a purple colour before the thickest part shows any degree of heat; to prevent which the heat must be ...
- Hammers
- (1) Drive piece of iron rod in eye to hold head by. Make full red hot, lay rod on edge of slack trough, harden the largest end, then turn small end in water, watch for temper in face, then the same to...
- Lathe Mandrel
- (1) Have the water lukewarm, and a little soapsuds in it. Bring the mandrel to a cherry - red, catch by the end in tongs, and be sure to dip slowly and vertically to the bottom of the tub. If moved si...
- Mill Bills
- (1) Get the point of the bill red - hot, put it on the ground to cool, try it with a saw file. If you cannot cut it, it is Mushet's steel. Treat as follows:- Get bright red, work out a little at a tim...
- Mining Picks
- In the first place, a good charcoal fire is necessary; next, good steel, and then a good light hammer with a smooth - faced anvil. A pick should never be upset, or hammered endwise, nor raised above...
- Saws
- (1) After toothing comes hardening, the toothed plates being heated to a light cherry - red, and then plunged into a bath composed of whale - oil, tallow, rosin, and beeswax. The plates, after hardeni...
- Springs
- (1) Harden right out, and then temper by flaring off in oil. If they are flat springs, a good way to harden them would be to get them red hot, and lay them on a fiat iron surface, covered with water, ...
- Taps And Dies
- (1) Rose says taps should be heated for hardening in charcoal fire, slowly to a cherry - red, and then dipped perpendicularly into clean water. The water should be made sufficiently warm to feel pleas...
- Steel Tools Generally
- (1) Softening. (a) Heat your steel to dull redness, hold it in some dark or shady nook or 3 corner until you can just see the least possible tinge of redness, then cool immediately in water at the ord...
- Steel Tools Generally. Part 2
- The temper greatly depends on the quantity of carbon that is in the steel. This the practical man soon finds out, and he tempers or draws down the tool accordingly. In Switzerland, razors, pocket - kn...
- Steel Tools Generally. Part 3
- The face of the end so hardened must be cleaned either with a piece of emery - paper or on a grindstone - either will do, as long as the part to be tempered is cleaned so that the colour can be seen w...
- Steel Tools Generally. Part 4
- The traversing mandril is made of the very finest steel to be obtained, and as it has to be bored through, and is not of sufficient substance to admit of welding, the nose is in the solid with it. In ...
- Steel Welding
- The following abstract of a paper by G. Newcombe, the secretary of the Cleveland Iron Trade Foremen's Association, will be found a valuable addition to the literature of the subject. Conditions Newc...
- Steel Welding. Continued
- If the destructive effect of oxygen is so apparent on a small sample of iron, an approximate opinion may be formed of the great loss resulting from its action on large masses. In proportion as we obta...
- Selection Of Iron Suitable For Welding
- Before closing this subject there is one matter nearly connected with welding which has not received that careful attention that it demands, and which future interests will require - the selecting of ...
- Nature Of Welding
- In the address of Jordan, President of the Societe des Ingenieurs, delivered at the annual meeting of that society in Paris, a novel explanation of the welding of iron is offered. Jordan says that wel...
- Steel Welding Recipes
- Steel (1) An excellent composition for welding cast - steel is prepared by boiling together 16 parts borax and 1 of sal - ammoniac over a slow fire for 1 hour. When cold, grind it to powder. The stee...
- Broken Spring Plate
- Get the length, and then take the part of broken plate which is easiest to handle, and upset it suitable for welding. Make a piece of iron | in. wide, quite thin at one edge, leaving the other about 3...
- Lacquers And Lacquering
- These terms, as generally used, cover such a wide ground, that no accurate definition can be given. The subject may be conveniently divided into the following sections. Brass Lacquers (1) Seed - lac...
- Lacquers And Lacquering. Continued
- (2) There are 2 kinds of Brunswick 3 black - viz., best and common. The way the best is manufactured is as follows:- In an iron boiler, over a slow furnace, 90 lb. foreign asphaltum is boiled for abou...
- Japanning And Japans
- (a) When finished wood, papier - mache, composition, or metals are varnished in the usual manner and left to dry in the air, the drying is in most cases imperfect, and the coating more or less uneven....
- Japanning And Japans. Part 2
- Then draw the sponge across the picture to take the gum off, or it will appear a network of cracks in a day or two. When dry, varnish the picture parts only, as the black will stand longer than varnis...
- Japanning And Japans. Part 3
- When the last coat is dry or hard, the whole surface should be well rubbed down with fine pumice sand, which can be purchased from oil and colour shops; but it must be fine, and if necessary dusted th...
- Lacquering Metallic Surfaces
- Following are miscellaneous recipes for lacquering metallic surfaces of all kinds. (1) For gold: 1 gal. alcohol, 1/2 lb. turmeric; macerate for a week, then filter, and add 2 oz. gamboge, 6 oz. shella...
- Lacquering Optical Work
- If an article has been lacquered before, that lacquer must, in the first place, be removed, and the article afterwards carefully cleaned and polished. When the brass has not been lacquered before, it ...
- Japanese And Chinese Lacquers
- Of late years, large quantities of Japanese lacquer - ware have been brought to this country in the course of trade, and sold often at remarkably cheap prices. The markets, indeed, have been quite gl...
- Japanese And Chinese Lacquers. Part 2
- A 10 - year - old tree, which some 5 years ago only cost 1 to 2 sen, now costs 10 sen, which, allowing even for the depreciation in the value of paper currency, shows a rise of about 500 per cent. Th...
- Japanese And Chinese Lacquers. Part 3
- It is also known as yeda urushi, or branch lacquer. The sap obtained from the first 5 cuts above each notch is poor, containing, as it does, a large proportion of water; the middle 15 cuts produce th...
- Various Kinds Of Lacquer And Mixtures Used
- (A) For Plain Work Ki-urushi (crude lacquer) is the generic name by which all lacquer obtained from the trunks of live trees is known. It forms the basis of nearly all the various mixtures used in ma...
- Various Kinds Of Lacquer And Mixtures Used. Part 2
- It should be noticed that whenever lampblack is mentioned as a mixture, it is used for the superior kinds, wood - or coal - soot being used for inferior articles. Implements and Materials used in the ...
- Various Kinds Of Lacquer And Mixtures Used. Part 3
- Next, a coating of Sabi is applied with the spatula, to hide the texture of the hempen cloth, and the article is again put in the press for 24 hours. Next, a coating is given of No. 1 Jino - ko, appli...
- Various Kinds Of Lacquer And Mixtures Used. Part 4
- (h) Kaki - awase (mixture), or Kuro - shunkei (black Shunkei), from the name of its inventor. In this class of goods the wood is given a basis - hardening coat of branch lacquer mixed with lampblack, ...
- Various Kinds Of Lacquer And Mixtures Used. Part 5
- That all lacquer, even that sold as pure lacquer, undergoes some adulteration, is rendered evident from the fact that, in accordance with a strange custom peculiar to the lacquer trade, the retail man...
- Mods Of Making Gold Lacquer
- (A) Togi - Dashi (Bringing Out By Polishing) The article having been subjected to the first 22 processes, as described in making Honji (Class I.), is then treated as follows:- The picture to be tran...
- More Common Kind Of Flat Gold - Lacquer Painting
- Instead of tracing the design in roasted lacquer, it is done with a mixture of powdered Tono-ko add water, and the impression is transferred to the articles with the whalebone spatula as before. The r...
- More Common Kind Of Flat Gold - Lacquer Painting. Part 2
- In making raised lacquer on inferior articles, the methods do not vary much from the good kinds; the work is merely less carefully executed. The saving is in the quantity and quality of the gold - dus...
- More Common Kind Of Flat Gold - Lacquer Painting. Part 3
- Objects in lacquered wood ornamented with paintings are termed in Japanese Makiye, a word which signifies powdered or lacquered painting. The material best adapted for the work is kiruki, the wood ...
- Seshime (Branch Lacquer)
- This kind is obtained from the branches of the trees as described above; but the yield is only 1 per cent. in comparison with other lacquer. As, however, in working, the proportion of nearly 90 Per ce...
- Ro-Urushi (Black Lacquer)
- This is made by adding to crude or branch lacquer, about 5 Per cent. of the tooth dye (haguro) used by women, a liquor formed by boiling iron filings in rice vinegar, and exposing it to the sun for se...
- Lanthanum
- This is another member of the cerium group of metals. About 5 1/2 Per cent. of its oxide is present in orthite, 3 1/2 in cerite, and 3 1/4 in gadolinite. Its separation from the associated metals is a...
- Lead
- The two most important sources of metallic lead are its natural sulphide (galena) and its carbonate (white lead ore). The ore, when mined, is hand - sorted free from refuse, broken small, and washed c...
- Lead. Part 2
- Fig. 135. Fig. 136. Reverberatory Furnaces The employment of reverberatory furnaces for smelting galena depends upon the double decomposition of the lead sulphate obtained by the roasting and...
- Lead. Part 3
- At the end of one hour, moat of the lead is run off; after 1 1/2 hour, the ore is thoroughly stirred of from both aides ; and at the end of 2 noun, the first fire is complete. (2) the heat is urged to...
- Lead. Part 4
- With a view to economy, the cheapest iron matters were long used ; but this plan has been given up on account of the excessive corrosion caused, and the rapid destruction of the twyers. It was only in...
- Lead. Part 5
- Condensing Vapours The fumes produced in the various metallurgical operations with lead contain in suspension extremely minute particles rich in lead, sometimes in such proportion as to amount to 7 P...
- Lead. Part 6
- 2. Smelt with ore - hearths. Formerly water condensation was used, but damage having resulted to the foundations of the works, it was abandoned, and dry condensation substituted. The flues are arrange...
- Lead. Part 7
- Hence it is important that the chimney in which the flue terminates should be removed to a good distance from habitations, and, if it be practicable, should be erected on the summit of some neighbouri...
- Lead. Part 8
- Other chemical agents calculated to arrest the sulphurous acid may be suggested, such, for instance, as a soluble sulphide (e.g., the yellow liquor from alkali waste heaps, if available), or hydrated ...
- Lead. Part 9
- According, then, to the quantities of lead and silver present in the ore, the whole or part of these metals will have been dissolved by this second acid, but portions of these may, and generally do, r...
- Lead. Part 10
- Lead chloride is solublo in boiling saturated solution of sodium chloride (brine) to the extent of about 53} parts (=40 parts metallic lead) to 1000 parts by measure of boiling brine; whereas, on cool...
- Lead. Part 11
- The form of the furnace Is shown in Fig. 142, The arch a is 18 in. above the hearth at the lire end and only 6 in. at the chimney end. The fireplace b measures 5 ft. long by 1 1/2 ft. wide: the bridge...
- Lead. Part 12
- The kettle is provided with a conical cover furnished with doors, which can be opened for manipulating the contents, and a wide iron pipe proceeds from the summit of the cover to convey the steam and ...
- Lead. Part 13
- To sum up, the advantages of the steam process, as compared with the old 6 - ton Pattinson pots formerly used, are: - (1) saving of amount of fuel used; (2) saving of cost of calcination of the...
- Lead. Part 14
- Sheet - Lead As lead is made into sheets by rolling, the first process to which the softened and desilverized pigs are subjected is melting and casting into cakes of suitable size. About 10 to...
- Lead. Part 15
- The paper being a bad conductor of heat, prevents the lead from solidifying immediately it leaves the ladle, and as by long practice the workman always ladles out the same quantity of lead, the sheets...
- Lead. Part 16
- Fig. 146. Various devices have been proposed for shot - making, having for their object the abolition of the tower. One process consists in pouring lead upon a revolving table on which is placed a...
- Lithium
- This alkali - metal occurs in appreciable quantity in several minerals, besides being very widely distributed through all 3 kingdoms (animal, vegetable, and: mineral), in less perceptible proportions;...
- Lubricants
- Lubricants are substances employed to reduce friction. Friction may be described as the effect produced by two bodies sliding one. upon the other, which have upon their opposing surfaces minute a...
- Lubricants. Part 2
- Now, if an oil of very high viscosity, such as castor or rapeseed, were used to lubricate an engine of low horse-power, in all probability, instead of reducing the friction to a minimum, it would itse...
- Lubricants. Part 3
- The test is applied in the following manner:- The apparatus is placed where it is not exposed to draughts. The water-bath is filled by pouring water into the funnel d until it begins to flow out at th...
- Lubricants. Part 4
- (262 C); (11) mineral oils alone are not suited for the heaviest machinery, on account of want of body, and higher degree of inflammability; (12) well-purified animal oils are applicable to very ...
- Lubricants. Part 5
- Menhaden-oil . 511 Neatsfoot-oil . . 505 Olive-oil 504 Crude cottonseed-oil . 348 Lard-oil .... 13...
- Lubricants. Part 6
- Under those circumstances, the paraffin-oil acts even less energetically, and though traces of the metal may be found in the oil in an hour from the commencement of the experiment, yet it take...
- Lubricants. Part 7
- Oil treated with precipitated lead. Increase of weight in oil Increase )f weight of fatty acid in in 2 days. 8dys. 8mos. Linseed 14.3 per ...
- Lubricants. Part 8
- The test with regard to spontaneous combustion is one which ought on no account to be overlooked. It has no relation to what is termed the flashing-point of an oil. Scientific investigation seems t...
- Lubricants. Part 9
- (5) Common heavy shop oil. 30 pints petroleum, 20 of crude paraffin-oil, 20 of lard-oil, 9 of palm-oil, 20 of cottonseed-oil. (6) Frazer's axle-grease is composed of partially saponified rosin-oil-th...
- Lubricants. Part 10
- Summer. Winter. Per cent. Per cent. Tallow 18.3 223 Palm-oil 12.2 12.2 Sperm-oil 1.5 1.2 Soda crystal...
- Magnesium
- This metal is widely distributed in some of the common rocks ;, e.g. as carbonate in dolomite and magnesite, as sulphate in kainite and kieserite, and in many saline springs; and as chloride in car-na...
- Manganese
- When the metal manganese was first discovered in 1774 by Frederick Gahn, the celebrated Swedish mineralogist and chemist, in reducing it from the natural oxide in a small crucible, nobody could have f...
- Mercury
- Themostimportant ore of mercury (quicksilver) is the sulphide called cinnabar, identical in composition with the vermilion of commerce. The most important deposits of this mineral are at Almaden in Sp...
- Mercury. Part 2
- As the vapour must be cooled down as far as practicable, the natural draught is very slight, and a tall chimney, generally with a small fire in it, is needful to draw in the requisite amount of air th...
- Mercury. Part 3
- Each furnace it closed at the top by a hopper with 2 doors, the upper of which has a water joint ; 12 charges are made a day, and care is taken to open the upper door as little as possible. At the bot...
- Mica
- Mica is composed of silex, alumina, and potash. It is found in America, Switzerland, Siberia, Norway, Bohemia, and Russia. Siberia and the United States probably furnish the best and largest specimens...
- Mica. Continued
- These thin laminae are easily cut with a pair of shears into any desired form, and are then ready for any further process necessary to fit them for the purpose for which they are intended. The facili...
- Molybdenum
- This metal occurs sparsely in many iron ores, and passes into the slag and the pig-iron in the smelting; but it is found much more abundantly in molybdenite (molybdenum sulphide) and in wulfenite (lea...
- Nickel Ores
- The principal ores of nickel are magnetic nickeliferous pyrites, nickel arsenides (especially kupfer nickel, and nickel arseno-sulphide or grey nickel), and the hydrosilicates of nickel and magnesia. ...
- Nickel Ores. Part 2
- From the preceding considerations, the roastings are conducted in a manner to avoid oxidation, and especially silica-tization, of the nickel and cobalt. In general, reverberatory furnaces are used for...
- Nickel Ores. Part 3
- Sulphuretted hydrogen is then passed through the solution to separate the copper and arsenic present, and the solution is again filtered. After this the whole process is a wet one, in which nothing of...
- Nickel Ores. Part 4
- When the object is to produce metallic nickel, the addition of copper is omitted; the heating is urged, and the oxidizing actions are developed to the utmost; the carbon and silicon are first eliminat...
- Nickel Ores. Part 5
- The melting-point of nickel is too high to admit of zinc being introduced into it after the nickel is molten. The addition of 1/10 Per cent. of magnesium is said to improve the working properties of t...
- Niobium
- This rare metal usually occurs with tantalum, in the form of an oxide (Nb205), in the following uncommon minerals:- 51 1/2 to 78 percent. in columbite, 47 to 51 Per cent. in pyrochlore, 45 Per cent. i...
- Osmium
- This metal is met with chiefly in the natural alloy osmiri-dium, in proportions varying from 27 1/4 to 43 1/2 per cent., as well as in minor quantities in platiniferous minerals. It is obtained in the...
- Palladium
- This valuable metal occurs in most-platinum ores and in alloy with gold. It may be separated from other platinum metals by taking advantage of the fact that, in neutral solutions, mercuric cyanide giv...
- Platinum
- This metal occurs almost exclusively in the native state, but is seldom pure. Analyses of samples from Australia, California, the United States of Colombia, and the Urals, show 61) to 86$ Per cent. of...
- Potassium
- Salts of potassium (silicates and chlorides mainly) exist in several rocks, and in moat soils and mineral waters. The metal is prepared from the carbonate by reduction with carbon at a white heat. Aci...
- Rhodium
- This member of the platinum group of metals is prepared from the solution remaining after throwing down ammonio-platinum chloride, by precipitating by metallic iron, and fusing the deposit with 1 part...
- Rubidium
- This comparatively newly-discovered metal is widely distributed in minute quantities in the minerals containing other alkali metals, such as lepidolite (0.24 Per cent. of rubidium oxide), carnallite, ...
- Ruthbnium
- This member of the platinum group of metals occurs in osmiridium (1/2 to 6 1/2 per cent.) and platinum ores, and as sulphide in laurite. It is best prepared by Deville et Debray's method from the os...
- Selenium
- This element, which fills an intermediate place between tellurium and sulphur, occurs mainly in connection with the latter body, being found in association with native sulphur itself, and with the sul...
- Silver
- Occurrence This metal frequently occurs in the native state, sometimes in masses of great weight (5 to 10 cwt.) but more or less contaminated with copper, gold, and mercury. The most common ores are ...
- Silver. Part 2
- The samples are generally taken 3 times daily, viz: before, during, and after the day's treading, and they must be chosen from all parts of the mass. The treading increases and hastens the action of t...
- Silver. Part 3
- Thus:- Primary Reaction 2AgCl + Cu2S + NH2 = Ag2S + Cu2Cl2.NH2 Secondary Reaction 2AgCl + Cu2Cl2NH2 = Ag2 + CuCl2,NH2 It was also found that reversal takes place when a mixture of silver chlorid...
- Silver. Part 4
- Amalgamation is performed in a set of revolving barrels, one of which is shown in Fig. 160. It measures 2 ft. 8 in. long, and 2 ft. 8 in. and 2 ft. 10 in. in diameter at the ends and middle respective...
- Silver. Part 5
- The rousted ore is passed through a screen with 1600 holes to the sq. in., to remove any caked lumps or coarse particles, and thence passes to the amalgamating barrels, which do not differ in any esse...
- Silver. Part 6
- Sodium-Amalgam It has become pretty general to use a small proportion (say 1 to 2 per cent.) of sodium with the mercury employed for amalgamation. The object of this is to prevent the surface of the ...
- Silver. Part 7
- (1) Cupellation And Equation The process known as cupellation is performed with the object of separating silver from lead by the oxidation of the latter. In this country, it is mostly employed on the...
- Silver. Part 8
- A cherry-red heat is then maintained and a full blast is kept up, the litharge being washed in sweeps towards an outlet which requires to be deepened in proportion as the liquid metal sinks in the hea...
- Silver. Part 9
- The lead in the bath gradually becomes enriched in silver, and when it reaches a value of 70/. to 80/. a ton, it is removed to the cupellation furnace, already described. (C) Wet Methods This term i...
- Silver. Part 10
- (4) Hunt And Douglas's 'This process is based on the difference of solubility of the chlorides, and consists of the following operations.. The mineral, after being submitted to ordinary chlo-rination...
- Silver. Part 11
- Properties And Uses Metallic silver has a sp. gr.of 10.424 to 10.57, a pure white colour, and a fusing temperature of about 1904 F. (1040 C); it is extremely malleable and tough, and the be...
- Slag or Scoria
- The disposal of the enormous output of slag or scoria from blast furnaces has always been one of the serious difficulties of the iron trade. Taking an average of all the districts in England, for each...
- Slag or Scoria. Continued
- For Paving-Blocks There is, however, one exception to the numerous failures in slag-casting. It is known as Woodward's patent, and although there is absolutely nothing new in the process, still, thro...
- Slag-Shingle
- In 1871, the waste land for the deposit of slag at the Tees Iron Works being filled up, and the works of the Tees Conservancy having temporarily been brought to a standstill, it became of serious mome...
- Slag-Sand
- The next great step in advance, and which laid the foundation for several processes hereinafter mentioned, was the reduction of the molten slag, as it flows from the furnace, into a soft spongy kind o...
- Slag-Cement
- The next product to be described is the manufacture of what is called slag-cement. The word cement has sometimes been objected to in connection with this material, because it is generally manufactured...
- Slag-Cement. Part 2
- From this it seems certain that the hardening follows closely in proportion the quantity of water which becomes chemically combined, and that the slag-cement undergoes a similar change to that which t...
- Slag-Cement. Part 3
- Percent. Lima ...... 29.90 Silica ................. 25.15 Alumina .... 21.80 Iron protoxide 1.44 Manganese protoxide. 0....
- Slag-Wool
- One more application of blast-furnace slag is the manufacture of slag-wool, or silicate cotton, so called from its resemblance to cotton-wool. The first attempt at this manufacture was in 1840, by Edw...
- The Cleveland Slag Works
- In works where so many special manufactures have been developed, the arrangement of the building-the design, position, and working of the machinery at present used-must necessarily have been arrived a...
- Sodium
- The salts of sodium are abundantly and universally distributed, the most common and familiar being the chloride-common salt; the nitrate, carbonate, and sulphate also form considerable geological depo...
- Strontium
- This member of the alkaline-earth group of metals occurs in small proportions in sea water, and in many brine springs and mineral waters, as well as in most of the calcium minerals'; but its chief sou...
- Tantalum
- This curious metal occurs in small quantities in some ores of tin and tungsten, but more abundantly in the uncommon minerals tantalite (containing 49 1/2 to 76} per cent. of the oxide), columbite (22f...
- Terbium
- This metal is found abundantly in samarscite, a mineral containing compounds of niobic acid with terbium, erbium, iron, and yttrium; but it has not yet been completely isolated from its associate erbi...
- Thallium
- This metal is sparingly distributed in many kinds of iron-arid copper-pyrites, and in some lithia-micas,but occurs to the extent of 17 1/4 per cent. (with about 33 1/4 per cent. of selenium) in a new ...
- Thorium
- This metal exists as an oxide in some rare minerals, e. g. to the extent of 73 3/4 per cent. in orangeite, 59 per cent. in thorite, and 18 per cent. in monazite, as well as smaller proportions in orth...
- Tin 0res
- Only 2 ores of tin have any commercial importance; these are the peroxide, known as cassiterite or tinstone, and the sulphide, called tin pyrites. The former is by far the more important, and is the c...
- Smelting
- In this country, smelting is effected in a reverberatory furnace, as shown in Fig. 176, where a is the fire-door for cleaning the fire-bars; b, the draught-hole, sometimes opened during the skimming o...
- Refining Tin
- The crude metal obtained by the smelting, whether in the reverberatory or in the blast furnace, has to undergo a refining process. The two chief impurities are iron and lead, the former of which may v...
- Utilization Of Scrap Tin
- The vast heaps of scrap tin found about tinware works, and the quantities of refuse tin cans that form such an item in city waste, have often been made the subject of experiment to separate the tin co...
- Titanium
- This metal occurs chiefly in the 3 minerals anatase, brook-ite, and rutile, which consist of its pure dioxide, and contain 61 per cent. of the metal; it is also a frequent constituent of magnetic iron...
- Tungsten
- This somewhat uncommon metal occurs in considerable proportions in several minerals, the most important being wolfram (which contains 76 1/2 per cent. of tungsten tri-oxide), scheelite (80 1/2 per cen...
- Uranium
- This uncommon metal occurs as carbonate, phosphate, and tantalate in some rare minerals, but its only commercial source is pitchblende, which contains 40 to 90 per cent. of uranoso-uranic oxide. Sever...
- Yttrium
- This member of the cerium group of metals occurs to the extent of about 34 to 35 per cent. (calculated as oxide) in the rare minerals gadolinite and wohlerite. It has not been satisfactorily isolated....
- Zinc Ores
- Zinc is not one of the most common or widely distributed metals, and never occurs native. Three of its ores are utilized, viz.:- Red zinc ore, an oxide coloured red by associated iron and manganese ox...
- Zinc Ores. Part 2
- Fig. 181. Fig 183. Smelting : (6) English method. - The construction of the furnace used in the English method of zinc-smelting is illustrated in Fig. 182. The furnace consists essent...
- Zinc Ores. Part 3
- Besides the alloys in which zinc forms an essential ingredient (pp. 13-17,20-1,29-30,34-5,42), there is an immense consumption for coating iron plates to produce what is known as galvanized iron. Zi...
- Zirconium
- This rare metal is found in a few uncommon minerals, chiefly in zircon and hyacinth. It can be prepared as an iron-grey powder by heating together potassium zirconofluo-ride (obtained by igniting zirc...
- Aluminium continued from p. 45
- So much interest is just now being excited in the direction of cheap-ening the production of this metal, that no excuse is needed for introducing here in the form of an appendix some information on th...
- Aluminium continued from p. 45. Continued
- The largest item in this excessive cost of extraction is for the vessels in which the Na2CO, is heated in admixture with powdered coal. It has not hitherto been found possible to heat the mixture of N...