CATALOG OF THE MECHANICAL COLLECTIONS 43 



STATIONARY ENGINE, 1829 



U.S.N.M. no. 180010; original model; gift of Charles M. Blackford; not illus- 

 trated. 



This is an operating model of a simple steam engine made by 

 William M. Blackford, a lawyer and editor of the Political Arena 

 at Fredericksburg, Va., in 1829. At that time steam engines were 

 so rare that Mr. Blackford was induced to deliver public lectures on 

 the steam engine, using the model as an illustration. It is believed 

 that the model illustrates the general form of the simple steam engine 

 as it was being built about 1829. 



The model has a vertical, double-acting cylinder, with the piston 

 rod connected by a double pin joint to one end of a walking beam. 

 The other end of the beam carries a connecting rod that turns a crank, 

 crankshaft, and flywheel. A slide valve moves across the lower end 

 of the cylinder and is driven by an eccentric on the shaft through 

 a valve rod, bell crank, and eccentric rod. Steam is carried to the 

 upper end of the cylinder through a passage extending along the 

 whole length of the cylinder. 



"LIGHTHALL'S IMPROVED HORIZONTAL AND BEAM ENGINE", 1838 



U.S.N.M. no. 308639 ; original patent model ; transferred from the United States 

 Patent OflSce; not illustrated. 



This model was submitted with the application for the patent 

 granted to William A. Liglithall, of Albany, N. Y., April 14, 1S38, 

 no. 696. 



The engine is designed primarily for boat propulsion and permits 

 the use of a horizontal steam cylinder installed low within the boat 

 in combination with a beam working vertically as in a beam engine. 



The model is diagrammatic in form, is made of wood, and is not 

 complete. The engine represented is essentially a beam engine laid 

 upon its side so that the cylinder is horizontal and the beam is sup- 

 ported vertically. The patent drawing shows the cylinder placed di- 

 rectly upon the keelson of a boat with the beam held so that the lower 

 end is at the approximate level of the center of the cylinder. A long 

 connecting rod attached to the upper end of the beam reaches back 

 over the cylinder to a crank on the engine shaft, which is located 

 above the cylinder and back of it. 



MAUDSLAY AND FIELD MARINE ENGINE, 1842 



U.S.N.M. no. 251298; original patent model; transferred from the United States 

 Patent Office ; not illustrated. 



This model was submitted with the application for the patent issued 

 to Joseph Maudslay and Joshua Field, of Lambeth, England, June 

 11, 1842, no. 2668. 



