ts peculiar
properties.

_Fixed air_ admitted to alkaline air formed oblong and slender crystals,
which crossed one another, and covered the sides of the vessel in the
form of net-work. These crystals must be the same thing with the
volatile alkalis which chemists get in a solid form, by the distillation
of sal ammoniac with fixed alkaline salts.

_Inflammable air_ admitted to alkaline air exhibited no particular
appearance. Water, as in the former experiment, absorbed the alkaline
air, and left the inflammable air as it was before. It was remarkable,
however, that the water which was admitted to them became whitish, and
that this white cloud settled, in the form of a white powder, to the
bottom of the vessel.

Alkaline air mixed with _common air_, and standing together several
days, first in quicksilver, and then in water (which absorbed the
alkaline air) it did not appear that there was any change produced in
the common air: at least it was as much diminished by nitrous air as
before. The same was the case with a mixture of acid air and common air.

Having mixed air that had been diminished by the fermentation of a
mixture of iron filings and brimstone with alkaline air, the water
absorbed the latter, but left the former, with respect to the test of
nitrous air (and therefore, as I conclude, with respect to all its
properties) the same that it was before.

_Spirit of wine_ imbibes alkaline air as readily as water, and seems to
be as inflammable afterwards as before.

Alkaline air contracts no union with _olive oil_. They were in contact
almost two days, without any diminution of the air. Oil of turpentine,
and essential oil of mint, absorbed a very small quantity of alkaline
air, but were not sensibly changed by it.

_Ether_, however, imbibed alkaline air pretty freely; but it was
afterwards as inflammable as before, and the colour was not changed. It
also evaporated as before, but I did not attend to this last
circumstance very accurately.

_Sulphur_, _nitre_, _common salt_, and _flints_, were put to alkaline
air without imbibing any part of it; but _charcoal_, _spunge_, bits of
_linen cloth_, and other substances of that nature, seemed to condense
this air upon their surfaces; for it began to diminish immediately upon
their being put to it; and when they were taken out the alkaline smell
they had contracted was so pungent as to be almost intolerable,
especially that of the spunge. Perhaps it might be of us