MECHANICS AND USEFUL ARTS. 73 



filled with melted lead, which, readily adhering to the tin and iron, forms 

 a compact mass in the recess around the cylinder body. 



The following are some of the results of practice with an ordinary six- 

 pound gun (rifled, 15 grooves, and carrying the new projectile), recently 

 made at Chicopee, Mass., under the direction of a Board of Officers attached 

 to the Ordnance Department of the United States army, Major W. A. 

 Thornton, chairman. 



The gun was first placed at a distance of 674 yards from the target. The 

 quantity of powder used at each firing was one and one-fourth pounds, the 

 service charge for a six-pound round ball, while the weight of the new pro- 

 jectile was over 12|- pounds. Eighteen shots were fired at a cloth target four 

 feet square, fastened on a board frame eight feet square. The shots varied 

 from the centre, from three and one-half inches to four feet, fourteen of 

 them entering the boards. The gun was carried back to 867 yards, or nearly 

 half a mile from the target, elevated at such an angle as should carry a six- 

 pound round ball to the centre of the target, and fired. The shot passed 

 over the top of the board frame at an elevation of about twenty feet, cut off 

 four pine trees (one six inches in diameter) without deviating apparently 

 from a direct line, and was lost. This shows the greater range of shot from 

 rifled guns. This charge of one and a fourth pound of powder would carry, 

 by calculations in engineering, a round shot of six pounds weight to the tar- 

 get, and no more; but in this case, a shot of more than double Aveight goes 

 over the target at such a height and force as to probably double the distance 

 to the target. The gun was then lowered, and five shots fired, two of which 

 entered the board within about two feet of the centre. A twelve-pound 

 rifled gun was then placed in the same position (807 yards distant), and 

 nineteen shots fired. Five of these entered the board at from three and a 

 half to four feet of the centre. Great difficulties were encountered in arriv- 

 ing at exactness, inasmuch as the guns had no sights perfectly adapted to 

 them . 



At a subsequent trial, with the same weight of powder, projectile, and gun 

 as in the first described experiments, a range of at least three and one- half 

 miles was attained; beyond this point the course of the ball was lost; but 

 the entire range was supposed to be as great as four and one-half to five 

 miles. A like result, with the same conditions of powder and weight of 

 projectile, has probably never been equalled. 



In a report on the above experiment, officially submitted to the Secretary 

 of "War, the Board say : 



" The depth of the grooving in Mr. James's gun is so shallow, as in no 

 case to materially impair the strength of the gun, while it is sufficient to 

 firmly hold the projectile and compel it to take the rifle flight. The perfora- 

 tion of the largest in all instances, and the obtaining of the projectiles after 

 firing, freely indicate that they invariably impinged point foremost; and 

 farther, in having one imbedded in damp earth, its spiral motion was plainly 

 indicated in the sand to the close of the flight. The grasp of the rifling is 

 further shown by the increased range obtained while using the same charge 

 of powder and elevation, in projecting masses of double the weight of the 

 usual spherical balls. The merits of the projectiles consist in their answer- 

 ing fully the expectations desired of them their ready fabrication and 

 adaptation to guns, their ease of loading, as it required but little more force 

 to send the projectile to the bottom of the bore than is needed to move a, 

 body of like weight on a smooth surface; the certainty of the expansion of 



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