Connecticut western news., 1898-04-07

sMoKELEss POWDER BEFORE AND AFTER FIRING.
 inches in the gun, and the expansive force of the gas then served to further accelerate the shell during its travel through the remainder of the bore. This brought very high initial pressure upon the gun and prevented the use of sufficiently large charges of powder to give high velocities.
 It was found, however, that by con- pressing the powder into cakes the total area exposed to the flame was reduced, and hence the time of combustion was prolonged. The result was that the pressure was produced gradually during the travel of the shell toward the mug gle, the pressure being spread out, as it were, over a larger area of the bore. The resulting velocity of the shell was the same, the difference in the action of the powder being the same as that be- tween a blow and push, but there was the added advantage that the initial or maximum strain on the gun was less. The ideal powder would burn at such rate that sufficient gas would be gen. erated to maintain a constant pressure behind the shell throughout the whole length of its travel through the gun. At tine same time it should be consumed at such rate that no unburnt powder should escape with the gases.
 The smokeless powders, because of the small quantity of solid products of com bustion and the great volume and high temperature of the gases, enabled the artillerist to secure velocities far in excess of those obtained by the use of the old powders. Moreover, smokeless powders lent themselves to the forma. tion of powder grains which would in- sure the very best control of the con- hustion of the powder. We present illustrations of the Maxim Schupphaus smokeless powder, which is formed into multiperforated grains, whereby the burning area is regulated so that only a desired initial pressure is obtained, and the powder is consumed with such in- crease of bnrning area as to maintain a practically equal pressure behind the projectile throughout the gun.
 It is evident that solid cylinders of powder would decrease in area as they burned, and there would be corre- spending decrease in the amount of gas given off. If, however, the cylinder burns up on the interior by means of suitable perforations, the burning area, and therefore the volume of gases pro- duced, will increase. The accompanying engraving is from a photograph of some unburned and partially burned grains of Maxim Schupphaus smokeless cannon powder. The partially burned grains were picked up in front of the gun after some experiments in firing powder from gun too small for the grain of powder employed. They illus trate the action of the combustion of this powder ill the gun and demonstrate that the powder is consumed with the effects claimed by Mir. Hudson Maxim.
 It will be seen that two kinds of per. forations are employed, those ill the cylinder to the right Eeing circular and those of the opposite cylinder being quadrilateral in section, with two sides radial to the center of the cylinder. The latter form was adopted to secure a more even and complete combustion of | the powder. That this is done is shown by comparing the bulk of the solid sec- tions which remain in the two types of powder grain. Scientific American.