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386 JAMES WATT. 
them by means of movable pistons, was still in its in- 
fancy. Wheretore in Newcomen’s early engines, the 
piston was covered with water intended to fill up the 
vacancies between the circumference of this movable 
piece and the surface of the cylinder. To the great sur- 
‘prise of the manufacturers, one of their engines began 
one day to oscillate much faster than usual. After many 
examinations it was ascertained that on that day the pis- 
ton was pierced, that some cold water fell into the cylinder 
by little drops, and that by passing through the steam, 
they annihilated it rapidly. From this fortuitous inci- 
dent may be dated the entire abandonment of all exterior 
refrigeration, and the adoption of a watering pot, to shed 
a shower of cold water throughout the capacity of the 
cylinder at the instant of the piston’s descent. ‘The 
alternate up and down motion now acquired all the de- 
sired swiftness. 
But let us see whether there was not another equally 
important improvement effected also by chance. 
Newcomen’s first engine required the most uninter- 
rupted attention from the person who had to open and 
shut the cocks either to introduce the steam into the 
cylinder, or to throw in the cold shower intended to con- 
dense it. It happened on a certain day that this person 
was young Henry Potter.* The companions of this 
child were then at play, and their exclamations of joy 
tantalize him severely. He longs to go and join them; 
but the task entrusted to him would not allow of half a 
‘minute’s absence. His mind becomes excited; strong 
passion awakes his genius: he discovers relative con- 
nections of which he had never dreamt before. Of the 
* The name of this play-loving and ingenious boy appears to have 
been Humphrey Potter.— Translator. 
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