_a._ Vitriolic ether absorbs nitrous oxide in much larger quantities
than water.
A cubic inch of ether, at temperature 52°, combined with a cubic inch
and seven tenths of nitrous oxide.
Ether thus impregnated was not at all altered in its appearance; its
smell was precisely the same, but the taste appeared less pungent, and
more agreeable. Nitrous oxide is liberated unaltered from ether at a
very low temperature, that is, at about the boiling point of this fluid.
For expelling nitrous oxide from impregnated ether, and for
ascertaining in general the quantity of gases combined with fluids, I
have lately made use of a very simple method, which it may not be amiss
to describe.
The impregnated fluid is introduced into a small thin tube, graduated
to,05 cubic inches, through mercury. The quantity of fluid should never
equal more than a fifth or sixth of the capacity of the tube.
The lower part of the tube is adapted to an orifice in the shelf of
the mercurial apparatus, so as to make an angle of about 40° with the
surface of the mercury.
The flame of a small spirit lamp is then applied to that part of the
tube containing the fluid; and after the expulsion of the gas from it,
the heat is raised so as to drive out the fluid through the orifice of
the tube. Thus the liberated gas is preserved in a state proper for
accurate examination.
Impregnated ether, during its combination with water, gives out the
greater part of its nitrous oxide. During the liberation of nitrous
oxide from ether, by its combination with water, a very curious
phænomenon takes place.
If the water employed is colored, so that it may be seen in a stratum
distinct from the impregnated ether, at the point of contact a number
of small spherules of fluid will be perceived, apparently repulsive
both to water and ether; these spherules become gradually covered
with minute globules of gas, and as this gas is liberated from their
surfaces, they gradually disappear.
_b._ Alcohol dissolves considerable quantities of nitrous oxide.
2 cubic inches of alcohol, at 52°, combined with 2,4 cubic inches of
nitrous oxide. The alcohol thus impregnated had a taste rather sweeter
than before, but in other physical properties was not perceptibly
altered.
Nitrous oxide is incapable of remaining in combination with this fluid
at the temperature of ebullition; it is liberated from it unaltered by
heat.
Impregnated alcohol, during its combination with water, gives out
the greater part of its combined nitrous oxide: on mingling the two
fluids together, at the point of contact the alcohol becomes covered
with an infinite number of small globules of gas, which continue to be
generated during the whole of the combination, and in passing through
the fluid render it almost opaque.
_c._ The essential oils absorb nitrous oxide to a greater extent than
either alcohol or ether.
,5 cubic inches of oil of carui combined with 1,2 cubic inches of
nitrous oxide at 51°. The color of the oil thus impregnated was rather
paler than before.
Nitrous oxide is expelled unaltered from impregnated oil of carui, by
heat.
1 of oil of turpentine absorbed nearly 2 of nitrous oxide, at 57°. Its
properties were not sensibly altered from this combination, and the gas
was expelled from it undecompounded, by heat.
_d._ As well as the essential oils, the fixed oils dissolve nitrous
oxide at low temperatures, whilst at high temperatures they do not
remain in combination.
1 of olive oil absorbed, at 61°, 1,2 of nitrous oxide, but without
undergoing any apparent physical change.