Physico-mechanical experiments on various subjects, containing an account of several surprizing phaenomena touching light and electricity. Producible on the attrition of bodies. With many other remarkable appearances, not before observ'd. Together with the explanations of all the machines, (the figures of which are curiously engrav'd on copper) and other apparatus us'd in making the experiments / By F. Hauksbee, F.R.S.

  • Hauksbee, Francis, 1666-1713.
Date:
1709
Catalogue details

Licence: Public Domain Mark

Credit: Physico-mechanical experiments on various subjects, containing an account of several surprizing phaenomena touching light and electricity. Producible on the attrition of bodies. With many other remarkable appearances, not before observ'd. Together with the explanations of all the machines, (the figures of which are curiously engrav'd on copper) and other apparatus us'd in making the experiments / By F. Hauksbee, F.R.S. Source: Wellcome Collection.

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    w. m ] generally heightens the Effe&s of the Electricity y does not at all contribute to the encreafe of the Light; Nay, Light is producible by the Effluvia of one Glafs falling on another; but the Electrical Matter is not to be brought forth, by any {\ichfeeble Strokes or Impulfes as. thofe are. Prof, fl Thofe Lights (in fome Circumftances at leaft) are lejsfenfbly. off eel ed by the return of the Air^vhich are pro~ duPd upon an Attrition of ex haufted Glafs in Pleno, than thofe produc'd by the Attrition of Glafs full 6f Air inVacuo. For, in the former cafe, no great alteration was found in-the Light or Colour, till a certain quantity of Air was let into the in fide of the exhaufted Glafs. But in the lat¬ ter cafe, both Light and Colour were fenfibiy chang’d, at every admiffion of Air, on the out fide of the full Glafs. Prop, 4*. Of the various Lights produc'd from various Bodies by Attrition, or (which is equivalent thereto ) ther Concuffianand Agitation of their Parts * fome are much more confin’d to a particular Medium, as a necejfary Con? dition of their Appearance, than others are... That of Culinary Fire, is abfolutely limited to fuch ; a Medium as Common Air, Thofe of Amberf: Woolleny Ojfter-fbells, &cc. require a' Vacuum, or the nearefl: approach to it, and utterly dif- appear in a groffer Medium. The Mercurial Lights are yet unlimited, as to the condition of the Medium in which they appear. For, as they are producible in and in a rarefied Medium approaching thereto; fo I have alfo fhewn, That a Light or this kind may be made to appear even in Common Air it felL And^tlius much for the Phenomena of Electricity and Lights produc’d by Attrition. From all put together, 1 hope, fame- thing may arife,that may be ferviceable to theDeiign,of^4/w- xnJ> frue Knowledge, of the Caufes of fo fur frizzing Appearances. And m .any one fhould luckily Improve thefe ffort Hints for that jurpofe* I Ihall have obtain’d my End. F 1 N I S,.