explosion, and explosion cause loss, it is a loss by fire as _efficient_
cause. Smoke, an imperfect combustion, damages, in an insurance sense,
as well as flame, which is perfect combustion; and where there is
concurrence of expanding air with expanding combustion, the law settles
on the basis of a common account. It's all "heat as a mode of motion."

Explosions are the resultants of elemental gases, vaporization,
comminution, contact of different substances, as well as of the
specifically named explosives. With new processes in manufacture,
involving chemical and mechanical transformations, and other uses of
new substances and new uses of old substances, explosions increase. The
flour-dust of the miller, the starch-dust of the confectioner, increase
in fineness and quantity, and they explode; so does the hop-dust of
the brewer. In 1844, for the first time, Professors Faraday and Lyell,
employed by the British government, discovered that explosion in
bituminous coal mines was the quickening of the comparatively slow
burning of the "fire-damp" by the almost instantaneous combustion of the
fine coal-dust present in the mines. The flyings of the cotton mill
do not explode, but flame passes through them with a rapidity almost
instantaneous, yet not sufficient to exert the pressure which explodes;
the dust of the wood planer and sawer only as yet makes sudden puffs
without detonating force. Naphtha vapor and benzine vapor are getting
into all places. One of the latest introductions is naphtha extracting
oil from linseed, and then volatilized by steam superheated to 400 deg. F.
This combination reminds us, as to effectiveness, of the combination at
the recent Kansas City fire, when cans of gunpowder and barrels of coal
oil both went up together.

But it is the unsuspected causes of explosion which make the great
trouble, and prominent among these is conflagration as itself the