250 



EIGHTEENTH CENTURY. 



PT. III. 



and, secondly, I must tell you that the rods, i and 2, are so 

 placed that when the engine- end of the lever-beam is raised, 

 as in the figure, the stopcocks a and c are open, and b and d 

 are shut ; and when that end of the beam falls, b and d will be 

 open, and a and c will be shut. 



Let us now begin with the machine as we see it in the 

 figure. In this position of the beam the cocks a and c are 

 open ; therefore, the steam below the piston will rush out at 



FIG. 43 . 



A, B, Cold water tanks, c, Outlet for cold water. D, E, Pumps for drawing off hot 

 water and sending it along s, s, back to the boiler, p, Tight-fitting piston. 

 a, d, Cocks for letting steam into the cylinder, b, c, Cocks for letting steam out 

 of the cylinder. e t e, Pipe which carries steam from boiler to cylinder, o, o, Pipe 

 which carries steam from cylinder to condenser, i, 2, Rods connecting the cocks 

 with the lever-beam. 



c into the condenser, there to be turned into drops of water, 

 while the steam from the boiler, entering at a, will force the 



