Show the Evo evolution luton of mining N A OF L in the stone age mining took no capital and a minimum amount of experience the tools man employed probably consisted of if i stone hammer a horn of some soma wt sort for a pick a board for a shovel and a crude basket for hauling away the pieces of chert chart for arrow and spear tips which they grubbed out of shale and soft limestone beds 2 when steel became popular ther the type of mining changed to where holes were drilled by hammering on a piece of sharpened steel these ho holes as were then loaded with black powder and blasted thi the overhead cost for each heading was still very small i 3 with the advent of the pneumatic drilling machine costs took a substantial rise the outlay for each heading exclusive of labor rose to around many times the previous amount 1 aa 4 k 4 As development and prospecting have had to be done at increasingly farther distances from the main haulage ways speed has become essential sent ial necessitating better methods accordingly power driven mucking machines and two or more machine machane jumbos or drill carriages have replaced hand mucking and single machines until now the total outlay for each heading in a mechanized chani zed mine Is about |