Railway and Locomotive Engineering . dle from that point up to 175pounds pressure was gradual, but veryrapid from 17S to 200 pounds, with theresult that the total rising of ihc needle after the throttle was closed and whiletlie locomotive was drifting. The maxi-mum downward i)ull tm tlie needle was3 tiiis point ha\ing been reachedwhile the engine was being worked hardand running at high speed. Fig. IS shows a record of the secondroad test, which was made from Uticato Palatine Bridge. We cannot explainthe rising of the needle 1/16-iii. aboveihi- normal line at the start of this trip. pa
Railway and Locomotive Engineering . dle from that point up to 175pounds pressure was gradual, but veryrapid from 17S to 200 pounds, with theresult that the total rising of ihc needle after the throttle was closed and whiletlie locomotive was drifting. The maxi-mum downward i)ull tm tlie needle was3 tiiis point ha\ing been reachedwhile the engine was being worked hardand running at high speed. Fig. IS shows a record of the secondroad test, which was made from Uticato Palatine Bridge. We cannot explainthe rising of the needle 1/16-iii. aboveihi- normal line at the start of this trip. pand as much as the fircliox slicets. Cer-tain it is that these mysterious varietiesin expansion is the cause of much of thetrouble that has arisen in boiler inainten-aiice and it is gratifying to know that inthe light of such experiments as havebeen made under Mr. MacRains super-vision, much real progress towards a morethorough understanding of the causes offracture in some of the parts has beenmade. This, of course, will lead to new. / / 1 y ^ —- ^ ^ / „^f„„^ —^ / ^^JSSi/A f iSS -* /^ J^. /^ above the normal line was lS/16-in. Itis difficult to account for the rapid risingof the needle between the time that thepressure increased from 175 to 200pounds, unless it be that tlie needle didnot work in the stuffing box quite asfreely as it should have done, but wecannot see how that could have been, asthe packing in the stuffing aroundthe needle was very loose. Arrangements were then made tomake a road test, and the operation was IUt it will be noted tiiat it did not occuragain during the entire trip. The re-mainder of the record is nearly a repe-tition of what occurred on the first trip,the increase in the downward pull of theneedle, in our opinion, being due to theengineer who was running tlie engine onthis trip working the engine harder thanthe engineer did who handled the engineon the first test, the maximum increasein pull downward on the needle being5/16-in. The b
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Keywords: ., bookcentury1900, bookdecade1900, bookpublishernewyork, bookyear19
