. American engineer and railroad journal . or comparative work,is very reliable. The differences in temperature recorded are prob-ably correct within less than one per cent. The weight of sparks or cinders passing the heating surface isthe sum of those caught in the front end of the locomotive andthose passing out at the top of the stack. The sparks whicli ac-cumulated in the front end %vere easily collected and weighed. Ofthose which passed out of the stack, a portion only were collected,the sample being so chosen as to serve as a basis from which thevalue of the whole could be estimated. The
. American engineer and railroad journal . or comparative work,is very reliable. The differences in temperature recorded are prob-ably correct within less than one per cent. The weight of sparks or cinders passing the heating surface isthe sum of those caught in the front end of the locomotive andthose passing out at the top of the stack. The sparks whicli ac-cumulated in the front end %vere easily collected and weighed. Ofthose which passed out of the stack, a portion only were collected,the sample being so chosen as to serve as a basis from which thevalue of the whole could be estimated. The apparatus employedin this latter process is shown by Fig. 7. It consists of an invertedU-tube of galvanized iron, securely fastened to a movable frame,by means of which the tip, which constitutes one extremity ofthe tube, can be pro,iected across the top of the locomotivesmokestack. The outer end of the tube may thus be made com-pletely to intercept a portion of the stream issuing from the (GALVANIZED IRONiTUBE FASTENEDI TO SLIDING FRAME. Fig. 7. Spark Trap. stack, and the continuous action of this stream is sufficient todrive the intercepted portion through the cube and out at theother end. The gases pa^sing the tube bear the sparks on theircurrent, and they are collected in a bucket set to entrap themReference marks upon the sliding and the fixed frames permit thetubes to be placed in definite locations relative to the center ofthe stack. This device, when in service, catches everything ex-cepting the lightest soot, which is allowed to escape unaccountedfor. After assuming the cross-section of the stream issuing from thestack to be cut up, by a series of concentric circles, into one circularand several annular areas, as shown by Fig. 8, the small end of the AND RAILROAD JOURNAL. 257 U-tube wa3 placed in the position marked I and held there for 30minutes, the sparks collected durln;; this interval being credited tothis position. The tube was then moved to the position II, whe
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Keywords: ., bookcentury1800, bookdecade1890, booksubjectrailroadengineering
