Pieces of dry cork wood being put to the acid air, a small quantity remained not imbibed by water, and was inflammable.
Very dry pieces of oak, being exposed to this air a day and a night, after imbibing a considerable quantity of it, produced air which was inflammable indeed, but in the slightest degree imaginable. It seemed to be very nearly in the state of common air.
A piece of ivory imbibed the acid vapour very slowly. In a day and a night, however, about half an ounce measure of permanent air was produced, and it was pretty strongly inflammable. The ivory was not discoloured, but was rendered superficially soft, and clammy, tasting very acid.
Pieces of beef, roasted, and made quite dry, but not burnt, absorbed the acid vapour slowly; and when it had continued in this situation all night, from five ounce measures of the air, half a measure was permanent, and pretty strongly inflammable. This experiment succeeded a second time exactly in the same manner; but when I used pieces of white dry chicken-flesh though I allowed the same time, and in other respects the process seemed to go on in the same manner, I could not perceive that any part of the remaining air was inflammable.
Some pieces of a whitish kind of flint, being put into a quantity of acid air, imbibed but a very little of it in a day and a night; but of 2-1/2 ounce measures of it, about half a measure remained unabsorbed by water, and this was strongly inflammable, taking fire just like an equal mixture of inflammable and common air. At another time, however, I could not procure any inflammable air by this means, but to what circumstance these different results were owing I cannot tell.
That inflammable air is produced from charcoal in acid air I observed before. I have since found that it may likewise be procured from pit coal, without being charred.
Inflammable air I had also observed to arise from the exposure of spirit of wine, and various oily substances, to the vapour of spirit of salt. I have since made others of a similar nature, and as peculiar circumstances attended some of these experiments, I shall recite them more at large.
Essential oil of mint absorbed this air pretty fast, and presently became of a deep brown colour. When it was taken out of this air it was of the consistence of treacle, and sunk in water, smelling differently from what it did before; but still the smell of the mint was predominant. Very little or none of the air was fixed, so as to become inflammable; but more time would probably have produced this effect.
Oil of turpentine was also much thickened, and became of a deep brown colour, by being saturated with acid air.
Ether absorbed acid air very fast, and became first of a turbid white, and then of a yellow and brown colour. In one night a considerable quantity of permanent air was produced, and it was strongly inflammable.