STONE CUTTING In order to describe intelligibly the various methods of preparing stones for use in masonry, it will be necessary to begin with a description of the tools used in stone cutting, as the names of many kinds of dressed stones are directly derived from those of the tools used in dressing them.
With a view to securing uniformity in the nomenclature of building stones and of stone masonry, a committee of the American Society of Civil Engineers in 1877 * prepared definitions of stone cutting tools and a classifica tion of dressed stone and of stone masonry, and recom mended that all specifica tions be made in accordance therewith. The old nomen clature was very unsystem atic and objectionable on many grounds. The new system is good in itself, is recommended by the most eminent authority, has been quite generally adopted by engineers, and should therefore be strictly adhered to. The following descrip tion of the hand tools used in stone cutting is from the report of the American Society's com mittee.
"The Face Hammer, Fig. 39, has one blunt and one cutting end and is used for the same purpose as the double face hammer where less weight is required. The cutting end is used for roughly squaring stones, preparatory to the use of finer tools.
"The Carl, Fig. 40, has one blunt and one pyramidal, or pointed, end, and weighs from 15 to 20 pounds. It is used in quarries for roughly shaping stone for trans portation.
The Pick, Fig. 41, some what resembles the pick used in digging, and is used for rough dressing, mostly on limestone and sandstone. Its length varies from 15 to 24 inches, the thickness at the eye being about 2 inches.
"The Ax or Penn Ham mer, Fig. 42, has two oppo site cutting edges. It is used for making draughts around the arris, or edge, of stones, and in reducing faces, and sometimes joints, to a level. Its length is about 10 inches, and the cutting edge about 4 inches. It is used after the point and before the patent hammer.
"The Tooth Ax, Fig. 43, is like the ax, except that its cutting edges are divided into teeth, the number of which varies with the kind of work required. This tool is not used on granite and gneiss.
"The Bush Hammer, Fig. 44, is a square prism of steel whose ends are cut into a number of pyramidal points. The length of the hammer is from 4 to 8 inches, and the cutting face from 2 to 4 inches square. The points vary in number and in size with the work to be done. One end is sometimes made with a cutting edge like that of the ax.
"The Crandall, Fig. 45,
is a malleable-iron bar about two feet long, slightly flattened at one end. In this end is a slot 3 inches long and inch wide. Through this slot are passed ten double-headed points of }-inch square steel, 9 inches long, which are held in place by a key.
"The Patent Hammer, Fig. 46, is a double-headed tool so formed as to hold at each end a set of wide thin chisels. The tool is in two parts, which are held together by the bolts which hold the chisels.
Lateral motion is prevented by four guards on one of the pieces. The tool with out the teeth is 5i by 21 by 1k inches. The teeth are 21 inches wide. Their thickness varies from -a to of an inch. This tool is used for giving a finish to the surface of stones.
"The Hand Hammer, Fig. 47, weighing from 2 to 5 pounds, is used in drilling holes, and in pointing and chiseling the harder rocks.
"The Mallet, Fig. 48, is used when the softer limestones and sandstones are to be cut.
"The Pitching Chisel, Fig. 49, is usually of 1}-inch octagonal steel, spread on the cutting edge to a rectangle of k by 21 inches. It is used to make a well-defined edge to the face of a stone, a line being marked on the joint surface to which the chisel is applied and the portion of the stone outside of the line broken off by a blow with the hand hammer on the head of the chisel.
"The Point, Fig. 50, is made of round or octagonal rods of steel, from } inch to 1 inch in diameter. It is made about 12 inches long, with one end brought to a point. It is used until its length is reduced to about 5 inches. It is employed for dressing off the irregular surface of stones, either for a permanent finish or preparatory to the use of the ax. According to the hardness of the stone, either the hand hammer or the mallet is used with it.
"The Chisel, Fig. 51, of round steel of } to f inch in diameter and about 10 inches long, with one end brought to a cutting edge from } inch to 2 inches wide, is used for cutting draughts or margins on the face of stones.
"The Tooth Chisel, Fig. 52, is the same as the chisel, except that the cutting edge is divided into teeth. It is used only on marbles and sandstones.
"The Splitting Chisel, Fig. 53, is used chiefly on the softer, stratified stones, and sometimes on fine architectural carvings in granite.
"The Plug, a truncated wedge of steel, and the Feathers of half round malleable iron, Fig. 54, are used for splitting unstratified stone. A row of holes is made with the Drill, Fig. 55, on the line on which the fracture is to be made; in each of these holes two feathers are inserted, and the plugs lightly tiriven in between them.
The plugs are then gradually driven home by light blows of the hand hammer on each in succession until the stone splits."