28 ANNUAL OF SCIENTIFIC DISCOVERY. 



Several of the largest machine-shops in the United State? are now engaged 

 in the manufacture of these engines, under licenses from the patentee. 

 Among these we may mention the establishments of I. P. Morris & Co., of 

 Philadelphia; the Newark Machine Co., of Newark, N. J.; Cltite Brothers, 

 of Schenectady, and William Kidd & Co., of Rochester, New York; and 

 Nourse &. Caryl, of Boston. Mr. John B. Kitching has established a general 

 agency for the engine in New York City, where he sells machines of his own 

 manufacture, and those of the manufacture of other licensees. 



It is but an act of justice to the caloric engine to state that the claims that 

 are made for it of entire safety and great economy seem to be abundantly 

 sustained by competent testimony; and we do not forget that the only com- 

 petent testimony in the case is that of men who have themselves employed 

 the engines, or watched them diligently and intelligently in the actual per- 

 formance of their offices. Such testimony is that of Professor Henry, offi- 

 cially made to the Lighthouse Board, to the practical operation of an 18-inch 

 caloric engine in its application to DaboH's fog whistle, or trumpet. He 

 says: "It [the caloric engine] is very simple in construction, easily put 

 in operation ; . . . easily worked, and not liable to get out of order. . . The 

 quantity of fuel required to supply the necessary amount of motive power is 

 too small to be considered an item of importance. The furnace holds about 

 a peck of coal, and no addition to the fire was made during the time the 

 committee was making the examination, though the engine was constantly 

 in motion for several hours. But the properties which more particularly 

 recommend it for the purpose of signals are, that it offers not the least da^n- 

 ger of explosion, and no water is required for its operation/' 



LENOIR'S GAS-ENGINE. 



Considerable interest has been excited during the past year, in Paris, by 

 the exhibition of u working gas-engine, devised by M. Lenoir, a French 

 engineer. 



The machine in question somewhat resembles an ordinary steam-engine, 

 but its motive power is obtained by the combustion of the ordinary illumi- 

 nating gas, mixed with atmospheric air. In certain proportions, this mix- 

 ture is explosive, as gas-engineers well know. But in Lenoir's machine the 

 detonating proportion of two volumes of gas to one of air is avoided, and 

 the highest combination allowed is one of gas to nine of air. Besides, the 

 two are not brought into contact till they have entered the cylinder, when 

 they are ignited by a spark from a little Ruhmkorff apparatus, and the dila- 

 tation of the gases forces the piston forward with great force. When the 

 piston reaches the end of the cylinder, it is carried back a little way by the 

 momentum of the fly-wheel, opening a valve at the same time, and admit- 

 ting another supply of hydrogen and air, Avhich is ignited by an electric 

 spark, and so the alternate motion is established. The whole machine is 

 simple and beautiful, and the only question as to its utility seems to be the 

 very important one of economy. 



On this point M. Lenoir states, (1), that the prime cost of his machine is 

 only about half that of a steam-engine of the same power; and, (2), that even 

 in using street gas, at the rate of SI. 60 per thousand feet, the saving of fuel, 

 as compared with the steam-engine, is at least fifty per cent., and that they 

 hope to obtain the non-illuminating gas, which will answer the purpose just 

 as well, at one-sixth of the price mentioned. One disadvantage of the 



