A treatise on electricity wherein its various phoenomena are accounted for, and the cause of the attraction and gravitation of solids, assigned : To which is added, a short account, how the electrical effluvia act upon the animal frame, and in what disorders the same may probably be applied with success, and in what not / By Francis Penrose.

  • Penrose, Francis, 1718-1798.
Date:
1752
Catalogue details

Licence: Public Domain Mark

Credit: A treatise on electricity wherein its various phoenomena are accounted for, and the cause of the attraction and gravitation of solids, assigned : To which is added, a short account, how the electrical effluvia act upon the animal frame, and in what disorders the same may probably be applied with success, and in what not / By Francis Penrose. Source: Wellcome Collection.

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    % [ 36 ] would return to their firft and natural pojition, viz. point towards the center of the earth. So, as Mr. Haukfbee obfervesfcc in thefe fmall orbs of m/ cc matter we have fome little refemblances of the cc grand phenomena of the umverfe” Another thing obfervable was, cc that by put- cc ting thefe threads within a glafs, when they be- cc came extended, this pofition of the threads cc would be altered at any time on the approach “ of one’s hand, finger, or any other body, to cc the furface of the glafs.” This is fufficient proof that the light, or as it is generally called, the electrical effluvia pafs through the glafs, with as much eafe as water does through a fieve. O V One thing which feemed a little furprifing to Mr. Haukfbee was, that upon exhaufling the grofs air out of the tube or globe made ufe of in elec¬ tricity, what he called the power of attraction, would ceafe; but upon differing the air again to enter, it returned as vigorous as before. This muff be the cafe; for (as was before obferved) when¬ ever the grofs air is extracted by an air pump, the fluid remaining is nothing but light. So, whenever this attrition is performed on an ex- haufted globe (for want of the refiftance of the grofs air within, to force off the particles of air ground fo fmall as light, and thereby to make an expanfion or rarefaction round the glafs globe, which