An historical and philosophical account of the barometer, or weather-glass ... And a modest attempt from thence made towards a rational account and probable judgement of the weather / By Edw. Saul, A.M.

  • Saul, Edward, 1677-1754.
Date:
1730
Catalogue details

Licence: Public Domain Mark

Credit: An historical and philosophical account of the barometer, or weather-glass ... And a modest attempt from thence made towards a rational account and probable judgement of the weather / By Edw. Saul, A.M. Source: Wellcome Collection.

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    return back to what bears a more immedi¬ ate Relation to this Subject. 2. The Amofphere being fas we have remark’d above) of fo great Depth and Extent, and refting with its whole incum¬ bent Weight upon the Surface of the Earth, the general Preffure refulting from it, muft be great in Proportion. Let us fuppofe a cubical Foot of Water, taking it at the Loweft, to weigh 63 ftho’ fome of our Eng- li(h Authors have rated it at 76J Pounds; and that the Weight of the Air, as is evi¬ dent in a Pump, ordinarily fupports a Co¬ lumn of Water $3 Feet in Height. From thence it will follow, that the general Pref¬ fure of the Atmofphere, is equal to that of an Ocean of Water furrounding the Globe 3 3 Feet in Depth. And confequently that the Atmofphere impendent over England (computing it in fuperficial Meafure to be 39 Millions of Acresj amounts to more than Fifteen Hundred Thoufand Millions of Tuns Weight, viz. i>576j735> 875?000> Tuns. And fince it is the Property of all Fluids, to raife and buoy up, all fuch Bo¬ dies, which bulk for bulk, are lighter than themfelves, lighter than the Medium in which they float: From hence alfo it will farther follow, that in an Ocean of Air of fuch intrinflck Weight, there muft be a Counter- poife more than fufficient, to fupport a far greater