Show V 7 FV WA R 72 r only one round lost in four months driving that was the record made in this tunnel with four men at the breast two machinists and two at an average advance of feet a month by vent ventilating dilating with vs S tt S SP S S S effs S IA 18 HP I 1 patented jan 2 1917 other patents pending N C coupled coupled in ten seconds fifteen minutes after firing new clean air for the next shift 2500 cubic teet feet of it a minute 2000 feet inside A 16 inch line of flenoid reduced production costs 50 and raised labor efficiency in the same proportion one man carries carries feet on his shoulders and suspends the tubing from rom a wire y pegged to the root roof 20 feet a minute and in less than a week the saving in in y 0 r for the cost C 21 upkeep has more than paid y qa half the cost of metal pipe and one sixth as much to install write and ask Us why 01 r P 4 1 BAG 00 N established 1858 v 4 poplar st st louis mo V |