Copy 1
The naturalist's and traveller's companion, containing instructions for discovering & preserving objects of natural history and for promoting inquiries after human knowledge in general / [Anon].
- John Coakley Lettsom
- Date:
- 1774
Licence: Public Domain Mark
Credit: The naturalist's and traveller's companion, containing instructions for discovering & preserving objects of natural history and for promoting inquiries after human knowledge in general / [Anon]. Source: Wellcome Collection.
64/128 page 38
![[ 58 ] and fal ammoniac powdered ; the globe thus pre^ pared, was fufpended in the air about five yards from the furface of the ground; the cold produced by the ice and neutral fait congealed the moiflure of the air on the external furface of the globe in the form of ice. This condenfed body was care¬ fully fcraped off with a filver fpatula, and received into a wide-mouthed bottle well rinfed : when I had colledled in this manner fome ounces of condenfed matter, I proceeded on the follow¬ ing experiments. EXPERIMENT I. To know if it contained any fixed air, I put one ounce of the condenfed moiflure into a vial? the cork of which was perforated through the whole length, to admit the extricated air to pafs through : over the cork was tied a loofe bladder free from any air; I then placed the vial, thus prepared, in boiling water; the heat of the water extricating the fixed air from the condenfed moiflure, it efcaped through the perforation of the cork into the bladder, where it was col- ledled; the quantity of this air occupied a fpace, which of fimple diflilled water was equal in bulk to 1 f drachm. The vial, upon weighing it after the feparation of the air, was reduced a few grains lighter. To be more certain that a great part of this extricated air was fixed, I applied it to lime- water; a precipitation of calcareous earth en- fued, which convinced me of its prefence. (See Seft. 1Y. page 29.) E X P Er > is. .»*- -A t .. s](https://iiif.wellcomecollection.org/image/b30511495_0001_0064.jp2/full/800%2C/0/default.jpg)
