Show The Evolution of Mining r 1 r rF s sl F c I l t M 1 In the Stone Age mining took no capital and a minimum amount of experience The tools man employed employed employed em em- probably consisted of a astone astone astone stone hammer a horn of some sort for a pick a board for a a shovel and a crude basket for hauling away the pieces of chert for arrow and spear tips which they grubbed out of shale and soft limestone beds 1 z When steel became popular the type of mining changed chang d to where holes were drilled by hammering r. r on on n a piece of sharpened steel These holes were then leaded with black powder po r and bl blasted The overhead cost for each heading was still very small 1 f 1 I 3 With the advent of the pneumatic drilling machine costs took a substantial sub rise The outlay for each he heading ding exclusive of labor rose to around 5 many times the previous pre amount f 3 11 s I Rh tY N NAs As development and prospecting have had to be done at increasingly I farther distances from the main speed has become essential essential es es- es necessitating better meth Accordingly power driven mucking machines and two two-or two more more machine Jumbos or drill carriages have replaced hand mucking and single machines until now the total outlay for each heading in a 1 me mI mechanized mine is about |