THE YOUNG FARMER'S MANUAL. 159 



stone, or the operator will make bad work by damaging many 

 good blocks of stone, that might, by a skillful workman, be taken 

 out of the quarry of a very desirable size and form. Stone are 

 not very elastic, and the operator should bear in mind that he 

 cannot drive in wedges in the seams of stone as carelessly as he 

 may in a block of wood. Stone will break before they will ren 

 der, or give but little ; therefore it will not answer to drive in 

 wedges all in one place. 



205. A workman in a quarry needs a half score of wedges 

 many times. They should be about four or five inches long, one 

 inch and a half wide, and about three-eighths of an inch thick, 

 of the very best iron, and steel-pointed. These should be driven 

 in the seams not more than one foot apart, and all driven at one 

 time, by striking them alternately one or two blows at a time. 

 This will open a seam uniformly, without danger of breaking a 

 stone. But if a wedge be driven in at a corner, for example, 

 unless the stratum is very thick the corner will be very liable to 

 break off. "Where the courses are laid bare, having vertical 

 seams from two to four or five feet apart, and the strata from four 

 to twelve inches thick, the surface should be marked off in a 

 square form, of the size of which it is desirable to have the stone, 

 and then a row of holes may be drilled eight or ten inches apart 

 where the stone is to be broken, and iron wedges driven into 

 these holes until the stone separates. Two pieces of half round 

 iron should be placed in each hole, leaving a space in the middle 

 of each hole for a flat wedge to enter between the two pieces of 

 half round iron. When the strata are not very thick, and the 

 stone are such as may be broken with fire, the strata may be 

 broken by fire instead of drilling holes and separating with wedges. 

 It is usually best to drive most of the wedges at the end in lifting 

 a stratum of rather thin stone, although some wedges may be 

 driven on the side ; but if the wedges should be driven mostly 

 on one side, a stone will seldom break square across the stratum. 

 When the strata are rather thin, by cutting a groove with a cold- 

 chisel about an inch deep where it is desirable to break the stra 

 tum, if the wedges be driven in the side opposite the groove, 

 7* 



