8 



SCIENCE. 



Firing Apparatus of the New Hvdrogen-Blkning Locomotive. 



first with the Holland Hydrogen Process, and afterwards 

 with coal and wood. This comparison is practically suf- 

 ficient in a broad sense, yet for more exact purposes it is 

 to be expected that opportunity will soon be taken to 

 obtain the result in pounds of water evaporated per 

 pound of naphtha, and also to exhibit chemically a 

 specimen of the gas. We learn that the boiler of the 

 new hydrogen-burning locomotive, since built at Pater- 

 son, after having been tried with very small flue, has 

 proved that the highly expansive and volum nous 

 gas produced requires more room for its most ad- 

 vantageous combustion, and the small flues, are now be- 

 ing exchanged for larger. The production of steam 

 pressure was still more rapid and economical than in the 

 Flatbush experiments, but the heat was so 'unequally 

 distributed, and the fire so insufficiently vented, through 

 the small flues as to make it evident that they were not 

 adapted to do justice to gaseous fuel as had been ex- 

 pected. For the present, therefore, we are obliged to 

 content ourselves with the latest of the series of tables in 

 which the comparative results of Holland gas and com- 

 mon fuel have been reported. 



Steam. 

 Pounds. 



Time. 

 Minutes. 



30.... 

 40 



Naphtha, tfjPfcAa. 

 Gallons. 



steam 



9.9 .99 



3.21 .3« ; 

 9J4 2.14 .21 



8 T.07 .1 



Engine Moves Out. 



Naphtha, Tou , 

 Mmute. * a P htha - 



70- 

 80. 



5% 

 4 



3'A 



iM 

 4 



3 



3 



.16 

 ■13 

 •3 

 .08 

 .08 



.054 

 .146 

 •25 

 ■■3 



.16 

 .24 



■34 



•23 

 ■*3 

 •27 

 .18 

 .18 



Safety Valve Blowing Off. 



9.9 

 13.11 

 15-25 

 •°-33 



■7-94 

 19.27 

 20.61 

 21.41 



22.22 

 23.29 

 -■3.83 

 ->4-37 



6 1.07 J .) 



Bom Valves Blowinc 



On. 



This report concludes with a statement of the fuel used 

 in firing up to 120 lbs pressure in the same locomotive, 

 as follows, on June 20: Half a cord of hard wood, cost 

 S3. 75 ; a large quantity of loose pine stuff not measured ; 

 and two tons best anthracite steam coal, cost $10; out of 

 which about half a ton was left after reaching the above 

 pressure. Allowing half a ton of half-consumed coal left 

 in the furnace, say one-fourth of a ton in value, the net 



cost was over $10, against 73 cents for identical work 

 with the Holland gas ; 24.37 gallons of naphtha, costing 

 3 cents per gallon, being consumed. The boiler was 

 specially adapted for coal, but badly encrusted with 

 scale, to the equal disadvantage of both fuels. The dif- 

 ference in direct cost was more than eleven to one in 

 favor of Dr. Holland. The following description of his 

 fire gives some data for an explanation of this surprising, 

 and yet often repeated and verified, result : 



The maturer process attained in the experiment of April 29 (and 

 since usual) gave no light visible by day from without the cavern 

 where it was pen;, dark and stormy as the cave of -■Eo'.us. Raging, 

 roaring, vibrating with a vehemence that shook the iron monster 

 and the ground beneath, and vied with the increasing din of steam 

 from the valves above and under, it was a kind of ghostly noise as 

 w ell as heat, that to the more habitual organ of perception gave no 

 sign, but seemed causeless or supernatural. In vain we peered 

 through the mica in the door, or peeped and dodged at the small 

 orifice from which a scorching heat spurted fully two feet. Smoke 

 and smell had clean vanished from all parts long before ; no un- 

 consurned carbon anywhere escaped to lend the faintest lustre ; the 

 carbonic acid formed in the retorts of course came out transparent 

 and inodorous, and so did the hydrogen, with the product of its 

 combustion, the invisible gas called superheated steam ; in short, 

 there was nothing ot a nature to be seen or smelt in all this melee 

 of nature's great elements. Even the illuminating effect of heat 

 upon iron was lost through the expulsive pressure of gases in the 

 retorts, which doubtless projected the flame too far to heat the 

 thimbles that no longer enclosed it. and now stood, like all else, in- 

 visible. All ended and came to light again (save the carbonic 

 acid) in a delicate cloud of v acor that rose from the smokestack 

 scalding hot, but too pure to soil white cambric. 



To this description it is pertinent to add the following 

 remarkable fact since observed in the trial of the new 

 hydrogen-burning locomotive at the Grant Works, with 

 the small experimental flues referred to as having been 

 afterwards condemned. The fire had been turned down 

 low and the valves set so as to allow the steam gauge 

 to remain stationary at 120 lbs., which it did with perfect 

 steadiness, showing the peculiar controllability of the 

 heat in this process. After about half an hour of this 

 test, the experiment of turning on double water (steam) 

 i'tto the two water retorts was tried, and the valves were 

 set open for this purpose, without restoring the oil feed. 

 The fire was evidently unchecked, and no further notice 

 taken for a few moments, the engineer sitting with his 

 back turned toward the boiler, as the weather was cold ; 

 when a violent discharge from the safety valve suddenly 

 caused him to- jump nearly to the middle of the tender 

 from the unexpected shock. The steam had run up to 

 132 lbs., with which the valve was loaded, before a 

 change had been noticed, and so continued blowing off 

 indefinitely, showing a rate of evaporation many times 



