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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    [ 5° ] fubterraneous Steams break out, and rife In greater Quantities through the Chinks and Fiffuresof the Earth : Many of which, be¬ ing lodged in the lower Regions of the Airy may, to a greater Degree, augment the Gravity of it. For as each of thefe fepa- rately adding, are found by Experience to raife the Mercury ; they mufi confequently have the greateft EfFedt, when all of them (as It may fometimes happen) confpire to¬ gether in encreailng the Preffure of the Atmofphere, and elevating the Mercury in confequence of it. ii. In remarking thefe Extremes, as well as in afcertaining the juft and precife Limits to the Rife and Fall of the Mercury; the Situation of the Place where the Barometer Hands, muft always with due Care be con- fidered and regarded. If it be low, and near the Level of the Sea, it will vary three Inches; becaufe the Atmojphere above is of competent Weight and Depth to admit of it : If it be mountainous and far within . Land, the Mercury will not vary two Inches ; becaufe the Cylinders of the Air above are proportionably lighter and Snorter. And, agreeably to this, it is found by Experience in feveral Places, that the verv fame Baro¬ meter , ftanding at Fair in the Valley below, will, in advancing up to the Top of a Mountain, fmk to Stormy, though the Weather be exadtly the fame in both. From