400 TRANSACTIONS OF THE AMERICAN INSTITUTE. 



Oil one part at a time, which causes unequal expansion, and consequently 

 great friction and unequal wear. 



Mr. Eowell. — I have seen this engine at work, and it ran very smoothly, 

 and appeared to work remarkably well. It appears to be a perfect machiae. 

 The engine was slowed so that I could listen to the exhausts, and it ap- 

 peared to work perfectly. 



Mr. Joseph Dixon. — I would like to remark, in confirmation of what has 

 been said, that I saw this machine in operation for half an hour, and it 

 worked very beautifully and smooth. The speed was increased very high? 

 and then slowed so that I could hardly see it move. The exhaust was clear, 

 and I could not perceive any noise, and I concluded that it worked very 

 perfectly. What a further investigation would elicit I do not know; but 

 at present I think this engine will take a high place among those of ijta 

 class. 



The Chairman. — This is the only novel steam engine, of any importance, 

 which has appeared for the last few years. It has the advantage of two 

 cylinders and pistons, working at right angles on the crank, as on the com- 

 mon locomotive, yet the whole is one case. It is remarkably compact, and 

 requires no balance wheel. The pistons are necessarily rectangular, and 

 the power is applied very close to the shaft. The wear of the engine must 

 be determined by use. With, regard to its adaptability to many places 

 where comparatively small power is required, there can be no question. 



Dr. Eowell. — In regard to the wear of rectangular pistons, it may be re- 

 marked that slide valves, some of which are four or five feet area, wear 

 very even, and keep tight for a long time, 



Mr. Root. — In figure 1 we have a perspective view from the valve chest 

 side. In this figure, A is the case, or what may be called the cylinder, 

 and B is the valve chest ; C is the main shaft, and D is the valve stem, 

 which has a rotary motion ; the other external parts are not peculiar, with 

 the exception of the governor, which is. In figure 2 we have given a side 

 elevation of the steam cylinder, A, with the valve face removed. 



This valve and face is shown in figure 3, while the piston and its crank 

 shaft are depicted in figures 4 and 5 ; thus the main parts, constituting 

 nearly the whole engine, are presented in this number. 



In figure 2, E is one piston and F is the other ; they are both right-angled 

 and parallelograms in shape ; the inner one, F, is hung directly on the crank 

 pin, and slides up and down in tlie other one ; it will thus be seen that one 

 piston has a vertical motion, while the other works horizontally. Steam is 

 admitted to both these pistons at once through the openings in the valve 

 face, and clearance is given in the cylinder, as shown at G ; the openings, 

 H, are for the four exhausts. These exhaust and steam passages are 

 shown clearly in figure 3 ; in it the valve face is marked I, and the steam 

 ports G; the exhaust, H. These latter, where they issue from the annular 

 passage common to the whole, are shown in dotted lines ; from these the 

 steam passes into the cylinder which is cored out all around, so that the 

 exhaust steam may be taken out at either of the two points closed by tlie 

 screw plugs shown in the engravings. The valve itself is a simple metal- 

 lic ring, shown isolated, at K, figure 3; the central orifice fits the eccentric, 

 X/, and this eccentric is driven by the stud on the end of the crank pin, sp 



