274 



DYNAMITE-GUN, THE. 



swung into any desired position and range. 

 The adjustment is further assisted and made 

 stable by means of guys placed on either side 

 of the base, the length of which can be altered 

 and fixed by turning the hand-wheels. Com- 

 pressed air or steam is introduced to the gun 

 from below, and passes up through the center 

 of the base, the pipe connecting with one of 

 the trunnions (which are hollow) ; thence it is 

 introduced into the pipe shown at the side of 

 the gun. This pipe leads into a valve which 

 i* A continuation of the breech, and is shown 

 as under it, and which is connected with it by 



deflection that would be occasioned by a side- 

 wind. Its center of gravity, it will be ob- 

 served, is some distance forward of its center 

 of figure. A side-wind, therefore, acting most 

 upon the lighter rear part, would have the 



THE I>YNAMITE-GUN. 



the short passage that may also be perceived 

 in the figure. The projectile or dart (see en- 

 graving) consists of two parts. The forward 

 part is made of a thin brass tube, into which 

 the charge of dynamite is inserted. In front 

 of the charge is a mass of some soft material 

 into which is fixed a pin firmly held in its 

 place, and the end of the whole is closed by a 

 conical metal cap. The charge is thus pro- 

 tected from premature explosion in front by 

 the soft material, which acts as a kind of cush- 

 ion against only moderate blows; but when 

 the dart is thrown from the gun, the impact 

 against a firm body will drive the pin home 

 through the soft material with such force as 

 to ignite the fulminate at its end and bring 

 about the explosion which it is intended to 

 produce there. Provision has also been made 

 to allow a certain amount of air to act as a 

 cushion for the dynamite cartridge, and thus 

 contribute to lessen the shock of a sudden dis- 

 charge. The cartridge-tube is closed at the 

 rear by a wooden plug the second part of the 

 projectile which flares out toward the rear 

 till its diameter equals that of the bore of the 

 gun. The construction of the projectile gives 

 it the power to correct, to a certain extent, the 



tendency to deflect it so as 

 to turn the head of the dart 

 into the wind, and that ac- 

 tion would, in a measure, 

 tend to keep it in the line 

 of its trajectory. 



To discharge the gun, the 

 dart is inserted in the breech, 

 and a gas-check is placed in 

 "tion. A lever then be- 

 ing moved, the valve is 

 opened, and the air-pressure 

 is admitted. There being no 

 shock of detonation, it is 

 believed that the danger of 

 the cartridge exploding be- 

 fore it leaves the gun wil" 

 be reduced to a minimum. The applicatioi 

 of the projecting force is further tempered 

 through an automatic arrangement of the 

 valve -controlling mechanism by means r* 

 which air is admitted gently at first, enou| 

 to overcome the inertia of the project " 

 upon which full pressure is let on. Th( 

 flow of air is stopped as the dart leaves the 

 gun. For this gun are claimed the advanta 

 of lightness, making it manageable on smt 

 craft; freedom from report and flash, making 

 secrecy in its operation more feasible ; anc 

 cheapness, for the cost of such a gun is but 

 trifle compared with that of other guns 

 equal power of destruction. Moreover, tho^ 

 guns require heavy special machinery and man] 

 months of labor to complete them, while dy- 

 namite-guns like the one described can be built 

 in any well-equipped shop in a comparative!" 

 short time. In the experiments with a twc 

 inch gun a range has been attained of one mile 

 and a quarter under the application of a press- 

 ure of 420 pounds to the square inch. In the 

 four- and six-inch guns it is intended to use 

 pressures of 2,000 pounds and upward, and 

 the gain of a considerably longer range is an- 

 ticipated. 



