[Illustration: Fig. 2]

To use the apparatus, open the stop cock D in the pipe C, leading to one
of the receptacles B, whereupon, owing to the lower pressure in the
cylinder B, the liquid carbon dioxide expands and rises to the top of
the cylinder A and forces the liquid carbon dioxide into the cylinder B,
the same as the superior steam of a boiler forces the water of the
boiler out when the same is tapped below the surface of the liquid. Now
upon opening the tap H, this superior gas forces out the mixture of
water and liquid carbon dioxide, which suddenly expanding causes
portions of the globules of liquefied gas to be frozen, and these, being
protected by a rapidly evaporating portion of the liquefied gas, are
thrown on the fire in solid particles. At the same time the water is
blown into a spray, which is more or less frozen. The fire is thus
rapidly extinguished by the vaporization of the carbon dioxide and water
spray.

* * * * *




SMOKELESS GUNPOWDER.

BY HUDSON MAXIM.


During the last forty years leading chemists have continued to
experiment with a view to the production of a gunpowder which should be
smokeless. But not until the last few years has any considerable degree