DOI Page / Citation link:
https://doi.org/10.11588/diglit.70300#0302
$68 kirby’s wonderful museum.
tually exhaling a variety of inflammable gases, and other ma-
terials, as hydrogen gas, or inflammable air, phosphorus, car-
bonic acid gas, and, occasionally, sulphureous vapours; at
times, separately, at others, in a state of union; and that the
most active of these are particularly evaporating in the low
stagnant marsh grounds, where these luminous meteors chiefly
make their appearance, and may at any time be collected with
the greatest ease, by placing over the surface of the soil an
inverted glass tumbler. Now, although these gases will not
spontaneouslvinflame in the ordinary temperature of the atmo-
sphere, yet they readily inflame from a great variety of natural
causes to which they are perpetually exposed. Electricity
may be a common cause of such inflammation. The heat
generated during the decomposition of the animal or vege-
table materials that may be locally decomposing, may be far
more than sufficient for that purpose, for we know it to be
sufficient to ignite hay-stacks, when the grass has been put
together too damp, and it is not improbable that some of
these materials may catch the illumination as from a candle,,
from a body in the immediate vicinity that is in the act of
spontaneous illumination.
Now the ball, or general mass of inflammable vapour,
being once lighted or inflamed from whatever cause, will
continue to burn so long as its inflammable principle remains,
and its combustible power may be more or less, in propor-
tion to its purity; whence, in some instances, it may pour
forth light, with little or no sensible heat; in others, the heat
combined with it may be sufficient to produce slow combus-
tion like that of a dunghill; and in others, palpable and rapid
flame. From the levity of the illumined or burning vapour,
it must necessarily change its place in various instances, ac-
cording to the current of air which it either finds, or by
burning, makes for itself; hence it must appear to move in
various directions, upwards and downwards, to the right and
to the left; it will seem to advance and then to recede, from
object to object, in a constant motion or dance before the
tually exhaling a variety of inflammable gases, and other ma-
terials, as hydrogen gas, or inflammable air, phosphorus, car-
bonic acid gas, and, occasionally, sulphureous vapours; at
times, separately, at others, in a state of union; and that the
most active of these are particularly evaporating in the low
stagnant marsh grounds, where these luminous meteors chiefly
make their appearance, and may at any time be collected with
the greatest ease, by placing over the surface of the soil an
inverted glass tumbler. Now, although these gases will not
spontaneouslvinflame in the ordinary temperature of the atmo-
sphere, yet they readily inflame from a great variety of natural
causes to which they are perpetually exposed. Electricity
may be a common cause of such inflammation. The heat
generated during the decomposition of the animal or vege-
table materials that may be locally decomposing, may be far
more than sufficient for that purpose, for we know it to be
sufficient to ignite hay-stacks, when the grass has been put
together too damp, and it is not improbable that some of
these materials may catch the illumination as from a candle,,
from a body in the immediate vicinity that is in the act of
spontaneous illumination.
Now the ball, or general mass of inflammable vapour,
being once lighted or inflamed from whatever cause, will
continue to burn so long as its inflammable principle remains,
and its combustible power may be more or less, in propor-
tion to its purity; whence, in some instances, it may pour
forth light, with little or no sensible heat; in others, the heat
combined with it may be sufficient to produce slow combus-
tion like that of a dunghill; and in others, palpable and rapid
flame. From the levity of the illumined or burning vapour,
it must necessarily change its place in various instances, ac-
cording to the current of air which it either finds, or by
burning, makes for itself; hence it must appear to move in
various directions, upwards and downwards, to the right and
to the left; it will seem to advance and then to recede, from
object to object, in a constant motion or dance before the