Miscellaneous experiments and remarks on electricity, the air-pump, and the barometer : with the description of an electrometer of a new construction ... / by A. Brook, of Norwich.

  • Brook, Abraham.
Date:
1797
Catalogue details

Licence: Public Domain Mark

Credit: Miscellaneous experiments and remarks on electricity, the air-pump, and the barometer : with the description of an electrometer of a new construction ... / by A. Brook, of Norwich. Source: Wellcome Collection.

    219/246 (page 193)
    will be cold enough to hold the tube by, while the remaining part of it goes on. [See Monthly Review, Vol. XLIX, page 584.] Tubes for barometers prepared in this way, 1. find generally, will fupport a column of mercury of the fame height: or, that inflead of a variation of half an inch, as fometimes happens with thofe made in the common wav, the former will very feldom vary half a tenth of an inch. Alfo, if they are well boiled, the mercury will always be fufpended to the top of the tube, and will not fall down to its proper height, till it be fhaken pretty ftrongly to bring it down; and fometimes I have had them fo ftrongly fufpended, that after the barometer has been fent many miles, it has been returned as ufelefs. One inftance of this kind happened at the time I was writ- ing this article. The fufpenfion of the mercury to the top of the tube occurred in the very firft tube that I heated before the common fire, though the C c adhefion