A Story Outline of Evolution 



an Italian invented a device which was in the nature of a 

 steam windmill, the steam being generated in a boiler and 

 then forced through a tube against the flat blades of a 

 wheel, which set the wheel in motion. The idea of the pis- 

 ton was conceived by a Frenchman. The early principle of 

 the steam engine was by throwing a jet of cold water into 

 the cylinder to condense the steam. This caused a vacuum 

 below the piston, which was forced down by atmospheric 

 pressure. The steam cock was then turned to admit fresh 

 steam below the piston, which was raised again. The open- 

 ing and shutting of the cocks was performed by hand, then 

 by a system of strings and valves and then by a system of 

 hand gear. By these crude methods, about three-fourths of 

 the steam admitted into the cylinder was lost and Its power 

 wasted. At this stage of the development of steam power 

 it was In about the same state of progress as was the sig- 

 nalling system used in France when the pole, beam and 

 movable arm were in use as a means of communication. 



The Idea which Mr. Watt applied to all the Ideas then 

 in use for the control and use of steam as a power was the 

 providing of a separate vessel In which to condense the 

 steam and which could be constantly kept In a state of 

 vacuum without any loss. This simple principle of physics 

 made the use of steam the greatest agency for power the 

 world has ever known. The use of steam as a power has 

 done more to develop the Industries of the world than have 

 all other agencies combined. Its far-reaching effect on the 

 advancement of civilization was, at the time of Its origin, 

 beyond the power of human comprehension. It will suffice 

 to say that, whereas, the time was when all the utilized 



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