Paving or Pavement. A layer or covering of stone or brick, carefully laid over roads, paths, halls, passages, etc, and to form stone floors in the interior of buildings. Pavements of flint and flags, in streets, are commonly laid dry, that is, in beds of sand or gravel; those of stables, courts, ground-rooms, etc. are laid in a mortar of lime and sand, or in lime and cement, especially if there be cellars underneath. Sometimes, after a floor of stone or brick has been laid dry, a thin stratum of mortar is spread over it, and worked into the crevices, to fill up all the joints. The several kinds of paving are as various as the materials of which they are composed, the adoption of which depends usually upon local circumstances and the expense: the following are the principal kinds.
1. Pebble-paving, frequently laid in ornamental design, is done with kidney-shaped stones, obtained from Guernsey and other places; it is extremely durable when properly performed.
2. Rag-paving, formerly much used in London: the stone is obtained from Maidstone, in Kent, whence the name of Kentish rag-stone; there are square stones of this material for coach-tracks and footways.
4. Square-paving, by some called Scotch-paving: by this was recently understood cubical stones, of blue whynn; they are, however, now nearly disused in London, owing to their inferiority of the next-mentioned.
5. Scotch granite; a hard material, usually of a bluish or reddish colour, with which the London road-pavements are formed.
6. Guernsey and Herm blue-granite; extensive quarries being now opened at the latter island, chiefly for the supply of the London pavements, for which purpose it is found to answer as well, if not better, than the Scotch. The stones are prepared of a prismoidal figure, by means of iron hammers, and are usually laid with their end downwards, bedded in gravel.
7. Purbeck-paving, of the blue sort, in large surfaces, and about 2 1/2 inches thick, make excellent flag pavements.
10. Newcastle flags are about two feet square, and two inches thick: answer well for out-offices.
11. Portland-paving, from Portland, sometimes interspersed with black dots. 12. Swedland-paving is a black slate, dug in Leicestershire; much used in paving halls, especially in party-coloured paving.
13. Marble-paving, frequently variegated with different coloured marbles, and sometimes inlaid in mosaic.
14. Flat-brick paving, done with brick laid in sand and mortar, or groute, as when liquid lime is poured into the joints.
15. Brick-on-edge paving, done with brick, laid edgeways, in the same manner.
16. Bricks laid flat or edgeways, arranged in herring-bone fashion.
17. Bricks set endways in mortar, sand, or groute.
18. Paving-bricks, made especially for the purpose.
19. Paving with ten-inch tiles.
20. Paving with foot tiles.
21. Paving with clinkers, for stables, etc.
There are many other kinds of paving, equally worthy of notice with the foregoing, but it would be needless to extend the description. We must not, however, omit to mention a beautiful imitation of mosaic, in various colours and designs, now manufactured of pottery-ware, some specimens of which we have seen at the Museum of National Manufactures and the Arts, in Leicester-square. Pavements of churches and other handsome buildings frequently consist of stones of various colours, but chiefly black and white, in squares or lozenges, artfully disposed. There needs no great variety of colours to make a surprising diversity of effect. It has been shown, that two square stones, divided diagonally into two colours, may be joined together, in checkers, sixty-four different ways, as each admits of four different situations, in each of which the other square may be changed sixteen times, which gives sixty-four combinations. A very beautiful example of a tesselated pavement, in black and white, is afforded in the extended floor of St. Paul's Cathedral, which is well worthy of examination by those who have occasion for works of that nature.
Having stated the various kinds of pavement as commonly practised by masons, we proceed to notice several deviations from that practice, which have been much talked of, and partially brought into use. The first we shall describe is the patented improvement of Mr. Abraham H. Chambers, of New Bondstreet, London; the object is for paving the horse and carriage-ways of our public streets. Mr. Chambers forms the bed of earth or gravel of the usual figure, which is a slightly elevated arch; this foundation is to be rendered as firm and solid as possible, by ramming, previous to laying down the stones, which are in form like the lower portion of a regular quadrangular pyramid, and are arranged so that the sides of each stone shall overlap those in the next row, as exhibited in perspective in the preceding cut. When they are thus laid uniformly and evenly, with their broadest surfaces or bases downward, a quantity of some of those stone-like cements, of which lime is the basis, or the British puzzolana, is to be poured between the joints, filling them to about one-third of their depth: when this has become hard, so as to cement the whole into one solid body, the remaining two-thirds of the interstices are to be filled with broken flints, granite, or other hard materials.
On each side of this roadway are to be constructed deep brick gutters, for the reception of the water, and the small portion of mud that may be formed; and midway, between each side and the centre of the road, lateral trenches are to be dug, to lead, by an oblique descent, into the brick gutters: these trenches are to be filled with broken bricks and stones, and serve as a filter, to convey nothing but the water from the middle of the road into the gutters. The patentee considers that a paved carriage-way, constructed upon this plan, will be extremely durable, and will be kept free from mud and sludge.
The patent triangular pavement is founded (as the inventor states), upon the reciprocal bearing and support of the stones. The pavement is formed of granite, or other hard paving stones, of the ordinary size, and each stone is laid or ranged in such a manner, with reference to the several contiguous stones, as that neither can be displaced the eighth of an inch, by any pressure or percussion, however great, in the ordinary use of the streets. The stones are not wedges or cubes, but formed as represented in the subjoined diagram, each containing a protruding or salient angle on the one side, and an indented or receding angle on the opposite side; the receding angle being formed to receive the salient one. Although the first cost of a pavement of this kind may be greater than ordinary, its probable greater durability will, most likely, more than compensate; besides, its level symmetry, cleanliness, and solidity of construction, derived by each part from the whole superficies, seem to be advantages attached to this species of pavement.
In Macknamara's patent pavement, the stones are comparatively thin, flat squares; their upper faces have two of the opposite sides of the quadrangle beveled off to an angle of about forty-five degrees; and underneath each stone the reverse sides of the quadrangle are beveled off in like manner, so that when laid together in the manner exhibited in the engraving on the next page, they may reciprocally support each other. Fig. 1 represents a plan of a street paved on this system; Fig. 2 exhibits a vertical section of the same, the roadway stones being numbered 1, 2, 3, 4, 5, (as shown on the plan); 6 6 are the gutter-stones; 7 7, those which abut against the curb. Fig. 3 gives a side view of three entire stones, exhibiting the reverse position of the beveled edges, by which the stones are mutually supported. Fig. 4 represents the opposite sides or edges of the same stones.
"By a careful attention to the figures, it will be seen," says the patentee, "that each and every individual block or stone mutually and reciprocally support, and are supported by, each other. This principle will be found to apply throughout, each block or stone being upheld by two adjoining ones, and, in return, mutually supporting others that are made to rest upon it. These blocks may be made of any convenient size; the principal object to be attended to is to make the bounding lines on the upper surface as perfect as the nature of the stones will admit. I shall here observe, that when blocks are used of large dimensions, it will be proper to groove their surfaces to form a better foot-hold for horses; and in order to identify my invention, and thereby endeavour to prevent any infringement on this patent, that it consists solely in working, cutting, or forming the sides of my blocks or stones, so that they shall make alternately obtuse and acute angles, with the upper surface of the block or stone which, being done, they may be so arranged or combined, that they will mutually and reciprocally support and preserve each other from the imperfection so generally found in the usual practice of paving."