Some considerations on the causes of earthquakes. Which were read before the Royal Society, April 5, 1750 / By Stephen Hales.

  • Stephen Hales
Date:
1750
Catalogue details

Licence: Public Domain Mark

Credit: Some considerations on the causes of earthquakes. Which were read before the Royal Society, April 5, 1750 / By Stephen Hales. Source: Wellcome Collection.

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    [ !0 ] and others who were up, faw a blackifh Cloud, with confiderable Lightning, juft before the Earthquake began; it was alfo . very calm Weather. And in the Hiftory of Earthquakes it is obferved that they generally begin in calm Weather, with a black Cloud ; and when the Air is clear juft before an Earthquake, yet there is then often Signs of plenty of in¬ flammable fulphureous Matter in the Air, fuch as Ignes fatui, or Jack-a-Lanterns, and the Meteors which are called falling Stars. Now I have fhewn many Years fince, in the Appendix to my Statical E/Jays, Expe¬ riment 3. page 280. the Effedt that the Mixture of a pure and a fulphureous Air have on each other, viz. by turning the Mouth downwards into a Pail of Water, a Glafs Veffel of a Capacity fufficient to hold about two Quarts, with a Neck about twenty Inches long, and two Inches wide ; then by putting under it in a proper Glafs Veffel with a long narrow Neck, a Mixture q(
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