484 TRANSACTIONS OF THE AMERICAN INSTITUTE. 



door sheaves, it lias been found diflScult to lubricate the working parts, 

 and in consequence, it is found after a year or two that the axle is ground 

 away. This is so serious that the door settles gradually until it comes in 

 contact with the floor, or with the track, and thereby prevents the moving 

 ■of the door, except bj?- great exertion. The roller sheave most effectually 

 prevents the occurrence of this evil, and herein is its principal advantage; 

 for, their being no friction between the axle and the plane upon v«^hich it 

 rolls, neither of them can wear away, hence the door must remain at the 

 height at which it was first placed, and continue to move with ease for any 

 length of time. This article illustrated by the accompanying engraving 

 is manufactured by Newman, Onderdonk & Capron, No. 1112 Broadway. 

 Mr. J. K. Fisher presented the following paper: 



Petroleum as a Steam Fuel. 



Mr. J. C. Ptichardson, C. E., has made experiments at Woolwich, the result 

 of which the London Times states to be that one ton of petroleum is " equal 

 for steam purposes to five tons of coal," and will occupy less room, and 

 will require fewer stokers, and so on. 



Mr. B. H. Paul controverts this. He concludes that there cannot be a 

 saving while petroleum is near its present price. 



Mr. Kichardson replies, claiming that Avith petroleum at £1^ per ton, and 

 coal at 15.S., and freight at.£1 per ton, "a return of £14. 15s. is made in favor 

 of petroleum." 



The Mechanics' Magazine reviews the discussion, and concludes that Mr. 

 Richardson has miscalculated — that it follows from his own data that the 

 balance will he £2.118. per ton against petroleum ; and it says that " while 

 the Woolwich authorities ma}^ possibly have good grounds for their alleged 

 report in favor of petroleum as fuel for ships, it is certain that Mr. Richard- 

 son has not shown such grounds to the public." The report of the engi- 

 neers appointed some months ago by our navy department was favorable 

 to the view that petrolenm may in some cases be used with advantage. 



When petroleum cost ten cents per gallon I proposed a plan for using it 

 to aid the combustion of smoke 'in locomotives. I read a paper on it before 

 this club, and published it in the Railway Review, which I then edited. But 

 the price soon rose so high that it seemed to me that it would not be econo- 

 mical, and I therefore did not pursue the subject. But since the explana- 

 tion of the geological relations of petroleum, by Dr. Stevens, it seems as if 

 the price of it cannot remain high, and may be expected to decline until it 

 can be used for steam fuel, at least in the cases I'eferred to in the reports. 



The method of combustion which I propose is an extension of what I 

 published two years ago. It is to vaporize the petroleum in a boiler, under 

 a pressure of about 150 lbs. per square inch. From the boiler it is to go to 

 the furnace in pipes perforated with minute holes, and to blow in jets into 

 the air, so as to be mixed and perfectly burned. The direction of the jets 

 may be such as to draw air into the furnace, as in D. K. Clark's method. 

 But for this present plan I propose to pump in the air under a pressure of 

 about 130 lbs. per inch, and to make the air enter in directions correspond- 

 ing to the petroleum vapor jets in order to cause perfect mixture and com- 

 bustion. Now I expect there will be no solid matter resulting from the 



