could not be referred to the subterranean noises
of volcanic countries—which, by an acoustic
illusion not yet, says M. Arago, satisfactorily
explained—and appear to issue from the air.

The sulphur-like odour of lightning has been
often described. This smell has been so strong
that it has sometimes almost suffocated travellers.
When Boyle, author of a General History of the
Air, was residing upon the borders of the Lake
of Geneva, the sulphureous smell of lightning
almost overpowered a sentry. After the British
ship Montague was struck in 1749 by a globe of
fire, the smell seemed to be nothing but sulphur.
At three in the afternoon of the 31st of December,
1778, the East India Company's ship Atlas
was struck by lightning, and a sailor killed at the
cross-trees, whilst a sulphureous smell was
developed which lasted throughout all that day and
the whole of the following night. The French
ship of the line Golymin was struck in 1812;
"and in going," says an eye-witness, "through
the ship after the accident, I was accompanied by
an officer and the master gunner. On arriving
at the great powder magazine in the after-part
of the ship I found it untouched, but when I had
the adjoining bread-room opened there issued
from it a thick and black smoke, and sulphureous
smell, which nearly suffocated us, although the
master gunner had opened the door a very little
way, and instantaneously reclosed it. We directly
afterwards entered the place and found no trace
of fire, but a complete overturning of its
contents; more than twenty thousand biscuits
had been tossed about without our being able to
find any traces of the path which the fulminating
matter must have followed to arrive at the spot."

Liebig found nitric acid combined with lime
or ammonia in rain-water which had fallen
during a thunder-storm. And it was in nitric
acid that Priestly, Cavendish, and Lavoisier
reunited the azote and oxygen gases of which the
atmosphere is compounded.

Lightning fuses metals. Aristotle, in his
Meteorology, says the coppering upon a shield
has sometimes been melted without the wood on
it having been injured. "Silver money," says
Seneca, "is melted without the purse which
contains it being injured; the sword is fused in
the scabbard, which remains unhurt; and the
iron of the javelin flows down the wood, and the
wood does not catch fire." Pliny says "that
gold, silver, and copper contained in a bag, may
be melted by lightning without the bag being
burnt, and without the wax upon the seal of it
being softened." In 1781, two French gentlemen,
M. de Gautran and M. d'Aussac, were
riding together in the neighbourhood of Castres,
when they were caught in a storm. A flash of
lightning at the same instant killed both their
horses and M. d'Aussac. The sword which M.
d'Aussac wore having been carefully examined,
it was found that an upper and a lower part of
the shell of the silver hilt, and about half an
inch of the point of the blade, were superficially
fused; and an oblong hole was pierced through
the piece of iron forming the end of the scabbard.
About thirteen inches from the hilt, a
small bit of the upper edge of the sword was
fused, and opposite this fusion the scabbard was
perforated. M. de Gautran, who was at the
side of M. d'Aussac, carried a large hunting-knife,
and the small silver chain which hung
from the hilt to the guard of this knife, was
found to be fused and detached. Fusion was
observable, also, on the silver mounting of the
hilt, on the silver end of the scabbard, and at
the end of the blade; but, unlike the scabbard
of the sword, the scabbard of the knife was not
burnt at the corresponding places. Most
singular are these cases, in which in apparently
identical circumstances one man is killed and the
other at his side is unhurt, or one scabbard
burnt through, and the other unscorched.
Lightning has been known to fuse the links of a
chain without leaving a trace of the fusion, or
of the fused links. In 1825, a gold chain was
broken by lightning while it was around the
neck of a lady, and the fragments were given to
M. Arago, who, however, could not discover any
trace of fusion upon them. The probability is,
that the lost links had been volatilised by the
lightning. For, when threads of gilt silk are
subjected to a strong current of electricity, the
gilt is volatilised, the silk threads remaining
unbroken. When ships have been struck by
lightning, bits of melted iron have sometimes
been found burnt into the deck. And a similar
thing once happened in Southwark. In the
month of June, 1759, a house was struck by
lightning, and the servants in one of the rooms
said "they saw it raining fire." The cause of
this appearance was the melting of a bell-wire,
which fell down in roundish drops, burning
their way into the wooden floor. Cases have
occurred in which lightning has not fused
metallic rods, but has softened or shortened them.

However wonderful these effects of lightning
upon metals may be deemed, the effects of lightning
upon stones are surpassingly wonderful.
Lightning vitrifies not merely exposed rocks, but
stones in the earth. In July, 1725, a flash of
lightning at Mixbury, in Northamptonshire,
struck upon a flock of sheep, killing five of them
and their shepherd. Near the feet of the shepherd,
two holes were observed, almost round
for half their depth, about three or four inches
across, and about three feet deep. The Rev. Dr.
Joseph Wasse examined these holes, digging
carefully on every side of them. Half way down,
each hole forked into two branches. In the
direction of one of these branch holes there was
found a very hard stone, about a quarter of a
yard long, five or six inches wide, and four inches
thick; and this stone was divided by a recent
crack, and its surface was vitrified.

A tower having been struck by lightning at
Bologna, Beccaria found that the mortar, of lime
and sand, had been fused into a greenish vitrification.
A man taking shelter under an oak in
Lord Aylesford's park, on the 3rd of September,
1789, was killed by lightning, which struck the
oak. When killed, the man held a stick in his
hand, and down this wet stick the lightning
descended into the ground, making a hole five