

1 6 MAC Leod, The Place of Science in History. 



Other improvements followed, and in 1769° Watt took 

 out his first patent. 



In 1775 Watt set up in business at Birmingham, 

 where, with his partner, James B0ULTON, 7 whose acquaint- 

 ance he had made in 1768, he opened a factory for the 

 manufacture of steam engines. The new enterprise was 

 very successful. Boulton occupied himself with the com- 

 mercial work, leaving to Watt the task of providing new 

 improvements. In the work of Watt we find, still more 

 than in that of his predecessors, the application of purely 

 scientific principles. For example, he studied the physical 

 properties of steam, among other things the relations which 

 exist between its density, pressure and temperature. He 

 is also the inventer of the indicator, which shows the 

 relation between the pressure of the steam and its volume 

 during the stroke of the piston in the cylinder. This 

 apparatus was employed by Boulton and Watt to measure 

 the work done by their machines. 



For a long time the steam engine had been applied to 

 no other use than the pumping of water. To allow of its 

 application to other uses it was necessary to find some 

 means of transforming the backward and forward move- 

 ment of the piston into a rotary movement. Watt 

 solved this problem by means of a crank and a flywheel, 

 the inerty of which ensured continuous movement. 

 Thanks to this arrangement, which is still in universal use, 

 the steam engine can be employed to work any sort of 

 mechanism. 



The second patent of Watt dates from 1781. From 

 this moment the steam engine took its modern form. He 

 ; later introduced the further improvements embodied in 

 his patents of 1782 and 1784. 



c In the same year Napoleon was born. 



'James Boulton was born at Birmingham on September 3rd, 1728. 

 lie died in the same town on the 18th of August, 1809. 





