The miners in Cornwall had been hampered by water flowing into their workings. When the upper strata had become exhausted they were tempted to go deeper in search of richer ores. Shafts were sunk into the lodes, and these were followed underground, but very speedily had to be abandoned through the influx of water. When the mines were of no great depth it was possible to bale the water out by hand buckets; but this expedient was laborious and ineffectual, as the water gained on the men who baled. Then whims were introduced, and by means of horse-power water was drawn up. But this process also proved to be but partially effective: in one pit after another the miners were being drowned out.
In the fen lands water was drawn up out of the drains and pumped into canals by means of windmills; and it is to this that Ben Jonson alludes in his play The Devil is an Ass, 1616, when he makes Fitzdottrell say: “This man defies the devil and his works. He does it by engines and devices, he! He has ... mills will spout you water ten miles off! All Crowland is ours, wife; and the fens, from us, in Norfolk, to the utmost bounds in Lincolnshire.”
But the use of wind as a motive power does not seem to have occurred to the Cornish miners, or perhaps it was thought to be too uncertain to be of much value for pumping purposes.
It is possible enough that Savery had read the suggestions of the Marquess of Worcester, and that this ingenious author gave him the first hint whither to turn to find the force required. But how he was led to steam is differently stated.
Desaguliers says that Savery’s own account was this: Having drunk a flask of Florence at a tavern, and thrown the bottle into the fire, he proceeded to wash his hands, when he noticed that the little wine left in the flask was converted into steam. He took the vessel by the neck and plunged its mouth into the water in the basin, when, the steam being condensed, the water was immediately driven up into the bottle by the atmospheric pressure.
Switzer, however, who was very intimate with Savery, gives another account. He says that the first hint from which he took the engine was from a tobacco-pipe, which he immersed in water to wash or cool it. Then he noticed how that by the rarefaction of the air in the tube by the heat, the gravitation or pressure of the external air, upon the condensation of the steam, made the water to spring through the tube of the pipe in a most surprising manner.
However it was that Savery obtained his first idea of the expansion and condensation of steam and of atmospheric pressure, he had now before him a new and untried power with which to deal, and he was obliged to approach it by several tentative efforts.
Before 1696 he had constructed several steam pumping engines to mines in Cornwall, and he described these as already working in his book entitled The Miners’ Friend.[24] He took with him a model to London and exhibited it to William III in 1698, and the King promoted Savery’s application for a patent, which was secured in July, 1698, and an Act was passed confirming it in the ensuing year.
Papin saw Savery’s steam engine, when exhibited before the Royal Society, he also witnessed the trial of his paddle-boat on the Thames. Returning to Marburg, of which university he was professor, he thought over what he had seen, and it occurred to him to combine the two contrivances in one, and to apply Savery’s motive power in the pump to drive Savery’s paddle-wheels. But it took him fifteen years to fit up a boat that worked to his satisfaction. “It is important,” he wrote to Liebnitz on 7 July, 1707, “that my new construction of vessel should be put to the proof in a seaport like London, where there is depth enough to apply the new invention, which, by means of fire, will render one or two men capable of producing more effect than some hundreds of rowers.” Papin’s boat that he intended to send to London was destroyed by some watermen, who feared the new invention might interfere with their trade.