THE STEAM-ENGINE. 



(THIRD LECTURE.) 



Methods of Connecting the Piston-Rod and Beam in the Double-acting: Engine. Rack and Sector. 

 Parallel Motion. Connexion of Piston-Rod and Beam. Connecting Rod and Crank. Fly- 

 Wheel. Throttle- Valve. Governor. Construction and Operation of the Double acting Engine. 

 Eccentric. Cocks and Valves. Single- Clack Valves. Double-Clack Valves, Conical Valves. 

 Slide Valve*. Murray's Slides. The D Valves. Seaward's Slides. Single Cock. Two- 

 way Cock. Four way Cock. Pistons. Common Hemp-packed Piston. Woolfa Piston. Me- 

 ttJlk Pistons. Cartwright's Engine. Cartwright's Piston. Barton's Piston. 



