^^'^J 



Figure 32. — The Arrangement of the Inside-connected adhesion ma- 

 chinery is shown here in plan view: (a) adhesion wheel, (b) crank, (c) 

 connecting rod, (d) crosshead guide, (e) piston rod, (f) secondary cross- 

 head, (g) cylinder, (h) secondary connecting rod, (i) counter shaft, (j) 

 eccentric, and (k) main crosshead. (From Sellers' Improvements.) 



the donor. Little turther thought was given to the matter until I 

 came across Sellers' statement that the model had been shipped to 

 Columbus. This and the striking similarity of the model described 

 by Sellers to the model on exhibit at the Ohio State Museum im- 

 mediately suggested that they were the same. 



Investigation revealed that the basic dimensions of the model are 

 identical to those Sellers lists in his Improvements (pp. 7-9) : 8-inch 

 truck wheels, 14-inch driving wheels, 18-inch track gauge, 4^2-inch 

 stroke, copper boiler, brass cylinders, and a tender mounted on 6 

 wheels. An examination of the machine in 1961 further revealed 

 that the valve gear, fitted to the rear driving axle, is identical to that 

 described in Sellers' British patent of 1847 (see fig. 29). Also, the 

 column attached to the frame to which the crosshead guide yoke is 

 fastened has an identical block and threaded hole, now plugged, at 

 its upper extremity. This can quickly be seen by referring to figures 

 30 and 31. This hole was the point of fastening for the crosshead 

 guide yoke for the upper cylinders. The smokebox, a square brass 



69 



