JAMES WATT. 37 



more beautiful. He proposed to establish a communication by 

 an open pipe between the cylinder and another vessel, the con- 

 sequence of which evidently would be, that when the steam was 

 admitted into the former, it would flow into the latter so as to 

 fill it also. If, then, the portion in this latter vessel only should 

 be subjected to a condensing process, by being brought into 

 contact with cold water, or any other convenient means, what 

 would follow ? Why, a vacuum would be produced here — into 

 that, as a vent, more steam would immediately rush from the 

 cylinder — that likewise would be condensed — and so the process 

 would go on till all the steam had left the cylinder, and a perfect 

 vacuum had been effected in that vessel, without so much as 

 a drop of cold water having touched or entered it. The separate 

 vessel alone, or the condenser, as Watt called it, would be 

 cooled by the water used to condense the steam — and that, 

 instead of being an evil, manifestly tended to promote and 

 quicken the condensation. When Watt reduced these views to 

 the test of experiment, he found the result to answer his most 

 sanguine expectations. The cylinder, although emptied of its 

 steam for every stroke of the piston as before, was now con- 

 stantly kept at the same temperature with the steam (or 212° 

 Fahrenheit) ; and the consequence was, that one-fourth of the 

 fuel formerly required sufficed to feed the engine. But besides 

 this most important saving in the expense of maintaining the 

 engine, its power was greatly increased by the more perfect 

 vacuum produced by the new construction, in which the con- 

 densing water, being no longer admitted within the cylinder, 

 could not, as before, create new steam there while displacing 

 the old. The first method which Watt adopted of cooling the 

 steam in the condenser was to keep that vessel surrounded by 

 cold water — considering it as an objection to the admission ol 



