The Arizona sentinel., 1890-01-18
CAUSE OF THUNDER.
How Sonorous Results Come from Inf1n|
itesimaI Causes.

lDeSlllldA SdUoCS'
Much has been written concerning the
/ cause of thunder, but for the most part
the explanations merely cause us to
wonder how such sonorous results can
come from such infnitesimal causes.
Thus line of nothing emanates from
nowhere; goes nowhere, acts for the
least conceivable period of time. Dur
ing this time the surrounding air be-
comes incandescent, and remains so for
an instant only, just long enough to
/ mark a path, the flash leaving by con-
trast blacker darkness than before.
! The air thus expanded by the heat
! from resistance contracts to its original
place.
Let us pass the first imponderable
! and see if we can not find results IN
! ponderable substances adequate to the
production of this deafening and reVer-
! berating effect which we call thunder
Take bulb having a neck curved up
so that the end may be immersed In
q vessel of water at a slightly higher
/ 1avel Solder in the bulb piece OF
n1atinum wire; fill the bulb ard pipo
with water, the upper end being sub
merged as stated. Connect the wire in
circuit with a battery of say two or
three Grove cells. The wire becomes
heated by the current, the water boils,
and we have the wire surrounded by an
atmosphere of aqueous vapor. Suppose
the vapor represents the cloud forma-
ton, and the wire the line of the cleo
trical effect, the lightning's path.
We have here our current in full con-
tact with aqueous vapor, which it rap
idly decomposes. The oxyhydrogen gas,
passing off in bubbles can readily be
collected in a receiver.
The law of diffusion of gases, of
course at all times operative, is not so
nearly instantaneous in its action as is
often supposed. If the water is blown
out of boiler while the furnace walls
are yet hot, and if the manhead is
knocked in, after time steam will
cease to escape. To all appearances the
boiler is full of air. Insert lighted
torch for better inspection; the light is
as instantaneously and effectually ex-
tinguished as if dipped into water. 1t
is simply an atmosphere of steam,
though considerable time has been al
lowed for diffusion.
The rise of the gases in the bulb
shows that they occupy very much
greater space than the vapor from
which they were derived. There is,
however, this difference between the
vapor in experiment and that of the
cloud: The latter is composed of
water finely divided, but, neverthe-
less, water in fact, while in the
bulb the vapor is not water, but steam
the gaseous condition, which, at at
mospheric pressure as in this case, oc-
cupies space 1,7O0 times greater than
the water from which it was derived.
The still further division, resulting in
the disintegratiOn of the steam in the
bulb into it's constituent elements, oXy-
gen and hydrogen, respectively, though
mixed-oxyhydrogen gas-results as al
ready stated, in greatly augmented vol
ume. Thus we see an immense dis
placement of air, how great is left to
our imagination to conjecture, as the
best constructed tables of volumes give
no exact and reliable information, as
the conditions are wanting. While the
electrical effect is at its height the
gases which are forming are highly
rarifed and thus occupy a relatively
large space.
With the decrease of electrical effect
and consequent heat, the repulsive effect
is decreased, and when the decline has
reached the proper point a recombina-
ton is instantly effected; the whole
volume of gas is instantly withdrawn,
leaving an insignificant small amount
of water in its place. The remaining
walls, moisture laden, rush in from all
sides to fill the void, producing terrific
conclusion. 1t is scarcely necessary to
advert to the rolling reverberatiOns,
for, with the prime cause ascertained,
the secondary effects naturally fol-
low. Intense electrical action will in
duce chemical action otherwise improb-
able; thus, hydrogen by diffusion will
come in contact and combine with
Large per cent. of oxygen, resulting in
ozone; and as a trace of ammonia is
found after thunder storms it seems
probable that through catalysis small
amount Of the liberated hydrogen may
unite with small amount of nitrogen.
We take it that the formation of these
two products tends to strengthen the
ypothesis.-Western Electrician.