Steam-power demonstratedIn 1699, Thomas Savery, at the weekly meeting at Gresham-College, demonstrated before the Royal Society a small model of his invention - a steam-powered water pump - which he patented 25 Jul 1698, "for raiseing water and occasioning motion to all sorts of mill-work by the impellant force of fire; which will be of great use and advantage for drayning mines, serveing townes with water, and for the working of all sorts of mills where they have not the benefit of water nor constant windes." Steam in a vessel condensed by an external spray of cold water caused a partial vacuum to lift water into the vessel from a lower sump, which was then forced further upward when more high-pressure steam entered.«[Ref: Philosphical Transactions of the Royal Society, London, vol. 21, p.228.] |
