CAPTIVE MOLECULES 



cylinder for condensing the steam, employing instead 

 an injection of cold water into the working cylinder 

 itself, thus enabling the engine to work more quickly. 

 It is said that the superiority of the internal condensing 

 arrangement was accidentally discovered through the im- 

 proved working of an engine that chanced to have an 

 exceptionally leaky piston or cylinder. Many engines 

 were made on this plan and put into practical use. 



Another important improvement was made by a con- 

 nection from the beam to the cocks or valves, so that 

 the engine worked automatically, whereas in the first 

 place it had been necessary to have a boy or man operate 

 the valves, a most awkward arrangement, in the light 

 of modern improvements. As the story is told, the duty 

 of opening and closing the regulating and condensing 

 valves was intrusted to boys called cock boys. It is 

 said that one of these boys named Humphrey Potter 

 "wishing to join his comrades at play without ex- 

 posing himself to the consequences of suspending the 

 performance of the engine, contrived, by attaching 

 strings of proper length to the levers which governed 

 the two cocks, to connect them with the beam, so that 

 it should open and close the cocks as it moved up and 

 down with the most perfect regularity." 



This story has passed current for almost two centuries, 

 and it has been used to point many a useful moral. 

 It seems almost a pity to disturb so interesting a tra- 

 dition, yet it must have occurred to more than one 

 iconoclast that the tale is almost too good to be true. 

 And somewhat recently it has been more than hinted 

 that Desaguliers, with whom the story originated, drew 



