Specimina ichnographica: or, a brief narrative of several new inventions, and experiments; particularly, The navigating of a ship in a calm, the improvement of the engine to raise water by fire, a new method of drying malt &c. For all which his Majesty has lately been most graciously pleas'd to grant his Letters Patent to John Allen, M.D / [John Allen].

  • John Allen
Date:
1730
Catalogue details

Licence: Public Domain Mark

Credit: Specimina ichnographica: or, a brief narrative of several new inventions, and experiments; particularly, The navigating of a ship in a calm, the improvement of the engine to raise water by fire, a new method of drying malt &c. For all which his Majesty has lately been most graciously pleas'd to grant his Letters Patent to John Allen, M.D / [John Allen]. Source: Wellcome Collection.

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    more, which is inconfiderable, after the great Allow¬ ance juft now mentioned. Therefore 3 Pound to the Foot will be amply fufficient to navigate a Ship after the rate of i Miles an Hour, and confequently be admit¬ ted as a ftandihg Rule for all future Calculations. Thus much may fuffice for an Enquiry, what Force and Power is neceflarily required to navigate a Ship in a Calm, which I have deduced, partly from the Spe¬ culation of rowing the Galleys, and from other Mens Writings and Obfervations; but chiefly from feveral of mine own Experiments,- by which, I apprehend, I am come to a great Degree of Certainty. In the next Place then I am to explain my own Me¬ thod, which, as I have hinted above, is by forcing Water, or fome other Fluid, through the Stern or hinder Part of the Ship into the Sea, by a proper En¬ gine or Engines placed within the Ship for that Pur- pofe. The other Fluids befldes Water that I am to make Ufe of for this Purpofe, are Air and Fire, as I have declared in the Specification of my Patent. Art. 14. I got a Sort of Force Pump fitted in thro5 the Bottom of a large Cock-Boat, with a Valve on the lower End of it opening upwards, fo as to let in the Water into the Pump-Barrel from under the Boat, and prevent its Return that Wayj a little higher up was a Spout about 3 Foot long fixed into the Barrel of the Pump horizontally, and the End of it went thro5 the Stern of the Boat, about half a Foot under Water; the Barrel of the Pump was about j Inches D z Diameter,
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