myself against uttering a prediction. It is never safe to prophesy,
unless you know, as the American humorist puts it. And in this case we
do not know, for a very dangerous rival, once defeated, but now full of
renewed vigor, has entered the lists against forged steel as a material
for ordnance. This rival's name is _wire_. Tempered steel wires can
be made of extraordinary strength. A piece of round section, only one
thirty-fifth of an inch in diameter, will just sustain a heavy man.

If, now, a steel tube, suitable for the lining of a gun, be prepared by
having wire wound round it very tightly, layer over layer, it will be
compressed as the winding proceeds, and the tension of the wire will act
as shrinkage. You will readily understand that a gun can be thus formed,
having enormous strength to resist bursting. Unfortunately, the wires
have no cohesion with one another, and the great difficulty with
construction of this kind is to obtain what gun-makers call end
strength. It is of but little use to make your walls strong enough, if
the first round blows the breech out. In the early days of wire this was
what happened, and Mr. Longridge, who invented the system, was compelled
to abandon it.

Lately, methods have been devised in France, by M. Schultz; at Elswick,
by Sir W.G. Armstrong & Co.; and at Woolwich, by ourselves, for getting
end strength with wire guns. They are all in the experimental stage;
they may prove successful; but I prefer not to prophesy at present.

The diagrams on the wall show the general construction of the modern
German, French, and English heavy breech-loading guns. The Germans have
a tube, a jacket, and hoops. The French, a thick tube or body, and
hoops. The English, a tube, a jacket, and an overcoat, as it may be
called. In each system of construction, the whole of the wall of the gun