. Electric railway journal . ing the holesfor the dynamite a punch bar driven by hammers, a soilauger with a long handle, or a churn drill are generallyused, although one company used a specially made hol-low pipe drill that is churned up and down, enough waterbeing used to make a thin mud. For deeper work up to 6V2 ft. very good holes aremade by tying small pieces of from one-eighth to one-half cartridge to a small straight lath or stick, startingat the bottom end and spacing them about 6 in. to 12 , leaving the last piece about 18 in. to 24 in. belowthe top of the ground. This distri
. Electric railway journal . ing the holesfor the dynamite a punch bar driven by hammers, a soilauger with a long handle, or a churn drill are generallyused, although one company used a specially made hol-low pipe drill that is churned up and down, enough waterbeing used to make a thin mud. For deeper work up to 6V2 ft. very good holes aremade by tying small pieces of from one-eighth to one-half cartridge to a small straight lath or stick, startingat the bottom end and spacing them about 6 in. to 12 , leaving the last piece about 18 in. to 24 in. belowthe top of the ground. This distributes the charge andpacks the earth tightly against the sides, leaving a cav-ity from 12 in. to 18 in. in diameter. Sometimes thedynamite is inserted into a long roll or cylinder of heavystiff paper and spaced as with the lath. In general, the quicker-acting dynamites make betterholes than the slower acting, heaving grades, a 40to 50 per cent straight grade being used in summerand a 40 to 60 per cent low-freezing extra grade. PREPARING TO BLAST A POLEHOLE; VIEW OF DYNA-MITE STICK being used in winter when the dynamite may becomechilled or frozen. Ordinarily no tamping is necessary, but for hardermaterial a small amount of tamping has the effect ofconfining the gases formed in the explosion, therebycreating a greater lateral pressure. Tamping generallyresults in a bridge being left over the cavity. By vary-ing the size and spacing of the cartridges, and theamount of tamping, the engineer is able in a few trialholes to obtain a system of loading to fit almost anycondition. Surface Cars Remodeled and Standard-ized at Kansas City Work Includes Removal of Inclined Platform, Re-arrangement of Seats and Redecorating The work of remodeling fifty-one cars of the 900Series type by the Kansas City Railways is nearly com-pleted. This is only one of the undertakings to bring all
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