PROCEEDINGS OF THE POLYTECHNIC ASSOCIATION. 535 



piston has performed one half of its stroke, in which position it is shown 

 in cylinder c. This lap may be made adjustable as to lerig'th by a sliding 

 piece, and therefore reg-nlates the expansion to any degree desired. 



Several variations can be made in this engine. It is not necessary that 

 the channels / and e be separate; they may be, included in one and may 

 terminate in the cylinders above the pistons, so as to omit the passage o 

 and 0'; the cylinders need not also stand in the position shown in the 

 engravings, but may be placed parallel to each other. Steam has been 

 described as the fluid used for the motive power, but water, gas, or other 

 fluid may be employed, and the engine also be employed as a pump. 



Mr. Hicks then gave a short description of the engine in its horizontal 

 form, which would be used in locomotives, steamboats, and many purposes 

 where great economy of steam is desirable, as the passages from cylinder 

 to cylinder are so reduced as to save nearly all the steam usually lost in 

 the ports. 



Fig. 4 represents an end view of engine D, with tjie caps to the crank- 

 shaft bearings; all the other parts being removed. A A inside of the 

 cylinders, show the ports'connecting the cylinders to each other, and to the 

 steam and exhaust ports. 



Fig. 5 represents a side view of the same engine, and the caps to the 

 bearings, with the other parts removed. 



Fig. 6 represents the engine standing on one end, with shaft and pulley 

 in place; also the steam and exhaust pipes I and H, as attached to the 

 bottom. 



Fig. 1 represents the pistons, crank, shaft, pulley, governor pulley and 

 connecting rods, disconnected, but in the positions occupied when in the 

 engine. The pistons show the ports and passages for steam, exhaust and 

 cut- off. 



Fig. 8 represents sectional view through B B, fig. 4; A B being steam 

 passages in the cylinders; C D being the exhaust. 



The exhibition of this new engine elicited an interesting discussion, in 

 which the novelty and value of the arrangement were fully explained. 



Warming Carriages. 



Mr. James Campbell illustrated by diagrams on the blackboard his method 

 of warming carriages. lie proposes placing in the box under the driver's 

 seat, or beneath the floor of tlie carriage, a tank filled with water, leading 

 from which are small iron pipes that pass around the interior of the coach. 

 The water in the tank is heated by a petroleum lamp. Mr. Campbell said 

 the necessity for such an apparatus in vehicles was very evident. In his 

 trade of coachmaking, the enquiry was often made by fliose ordering pri- 

 vate carriages, if some plan could not be devised for warming them, and 

 hence he was induced to experiment, and of the various plans tried, the 

 one here shown seemed best calculated to effect the object. . Carriages nov7 

 made weigh fron\ 1,400 to 1,700 pounds, and the entire weight of this appa- 

 ratus would not be over 75 pounds. 



Mr. Stetson said that this device appeared quite novel for warming car- 

 riages by hot water pipes, and using petroleum for fuel. The idea of 



