MILITARY ENGINES. 121 



have only one dolphin, whence their name. They are, however, from ten 

 to eleven calibres in length, whence they shoot with more accuracy than 

 the others, and have no cylindrical chamber, but run conical from the 

 beginning of the seat. The vent runs in obliquely, and the base mouldings 

 are cut off on the under side. Another kind of howitzer was invented by the 

 Russian General Count Schuvaloff in 1746, and called from him Schuvaloffs, 

 of which Jig. 16 is the side view and jig. 17 the horizontal section. 

 The bore, instead of a cylinder, was an oval with the long axis hori- 

 zontal, and was designed for giving a greater lateral spread to grape 

 shot than usual. They were kept a secret, and were, therefore, not 

 oval at the muzzle, but rounded, so as to appear externally like any other 

 howitzer. They did not, however, produce the expected effects, and were 

 soon abandoned. Other powers had long howitzers also, the so called shell- 

 pieces, as, for example, the Saxons, and these with the Russian unicorns 

 suggested to the French Colonel of Marine Artillery, Paixhans, the idea of his 

 bomb-cannon. This is a kind of very long howitzer {fig. 18) with conical 

 chamber, which exists in various calibres (our plate shows an 8-inch). 

 From these solid shot as well as shells can be fired. Their fire is more 

 certain than that of the common howitzer, and their effect very great. 

 They were first employed at the siege of Antwerp, where also Paixhans' 

 great mortar, constructed upon similar principles, was used. 



c. Mortars. Mortars are in all respects very similar to howitzers, save 

 that their trunnions, since they are only designed to discharge shot at a very 

 great elevation, are not in the middle, but quite at the hinder end ; there are 

 some, indeed, which have, instead of trunnions, only a cast foot, and which 

 can, therefore, be fired only at one angle. Internally the mortar is divided 

 like the howitzer, but the chambers have many different forms. The com- 

 mon chambers are the cylindrical [pi. S6, fig. 25) and the conical (fig. 29), 

 but there are some pear-shaped, the narrowest part in front, and some 

 spherical. The two last, however, being ineffective, are at present very 

 rare. Externally the mortar is divided (fig. 30) into the breech I, with the 

 trunnions G H, the reinforce G H E F, the second reinforce E F C D, and 

 the muzzle A B C D. On the second reinforce stand the handles or 

 dolphins. Mortars are shorter than howitzers, usually not more than three 

 calibres long, in order that the bomb may be introduced conveniently. 

 The mortar of Paixhans, however, was very much longer, to give a greater 

 range. In the weight of mortars the proportion is usually 15 to 20 pounds 

 of metal in the piece to each pound in bomb, so that a 30-pound mortar 

 weighs 60 times 15, or 60 times 20, i. e. 900 or 1200 pounds. Fig. 25 shows 

 a Prussian 50-pound mortar ; fig. 26, an Austrian 30-pounder ; fig. 27, the 

 same after Vega's construction, with conical chamber and the trunnions 

 a little advanced ; fig. 28, the French 10-inch mortar ; fig. 29, the Gomer 

 mortar with flat conical chamber and trunnions E C on the second 

 reinforce ; fig. 30, an English mortar. 



d. Cannon and Howitzer Carriages. The frame upon which the piece 

 is placed for use and for transportation is called its carriage ; the gun is 

 attached to it by means of the trunnions, and it is fitted also with all the 



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