An historical and philosophical account of the barometer, or, weather-glass, wherein the reason and use of that instrument, the theory of the atmosphere, the causes of its different gravitation are assigned and explained. And a modest attempt from thence made towards a rational account and probable judgment of the weather / By Edward Saul, A.M.

  • Saul, Edward, 1677-1754
Date:
1766
Catalogue details

Licence: Public Domain Mark

Credit: An historical and philosophical account of the barometer, or, weather-glass, wherein the reason and use of that instrument, the theory of the atmosphere, the causes of its different gravitation are assigned and explained. And a modest attempt from thence made towards a rational account and probable judgment of the weather / By Edward Saul, A.M. Source: Wellcome Collection.

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    C 2 7 ] is not only incredible, but found in FaT to be more than falls in Rain in a whole Year. For at Paris and Lijle (where the Mer¬ cury varies, as with us, near three Inches) the Quantity of Rain falling in one Year, by a Medium of fix Years, amounts to no more than 21 Inches in Height. At Zurich in Switzerland to 32 Inches. By the accu¬ rate Obfervations of Mr. Derham at Upmin- Jler in Efjex to 19 R By the Tables of Rain kept by Mr. Townley of Lancashire, it is bated by a Medium of 15 Years, at 41 Inches. But as thefe two Englijh Accounts, feem each of them to border upon oppofite Extremes, the mean Proportion of Rain falling one Year with another, and taking one Part of England with another, may be fairly eftimated at the perpendicular Height of 30 Inches. The Reafpn then, why the Air is hea¬ vier at one Time than another, cannot be from the Quantity of Vapours floating in it $ but fee ms rather to arife from there beine more Air on that Part of the Earth’s Sur¬ face, where fuch Preffure is encreafed. And this feems chiefly to proceed from the Winds. For Example : If the Wind, whieh is nothing but a Stream of Airfhouid blow upon any Place, and the Air, thus fet in Motion, fhouid be check’d in its Progrefs, or reflected upwards, by the Oppofition of Mountains and Hills; „ l) 2 or