Page:The New International Encyclopædia 1st ed. v. 18.djvu/181

* SIEGE. 143 SIEGE GUN. tion, an assault is delivered by the attacking force on one of the weakest points of the work. The assaulting party is providuil with explosives to be used in demolishing the palisades and simi- lar obstructions, and with ladders, planks, wire- cutters, and other implements to enable it to surmount and cope with the obstacles it may find. From the nature of the case, if the de- fender is prevented from receiving supplies, and the attacker can receive such reinforcements result of starvation. During the Franco-Prus- sian War the sieges of Strassburg, Metz, Paris, and Belfort were carried on under different con- FiG. 3. CASEMATE IN TRENCH (entrance from end). and supplies as he requires, the victory should normally be with the attacker. It may, how- ever, be only necessary for the defender to hold out until a relieving force more formidable than the attackers can reach the place. It is there- fore incumbent upon him to resort to other means to protract the defense. Having noted, for ex- ample, that an attack will probably be success- ful upon certain portions of his line, an addi- tional line would be constructed in rear of this portion, and so fortified that it can be held even if the first falls. His fire is so directed as to delay the attacker's trench work. His force, while not large enough to defeat the attacker in open combat, may be large enough to threaten him so frequentl.y as greatly to diminish his en- durance. Sorties are frequently made at night, Fig. 4. BATTERY ON OBOUND SLOPING FROM THE FORTHEBB. (Crosa section.) surprising the operations of the attacking force, destro3'ing its material, its work, and generally lowering its morale. The construction of the emplacements for the siege batteries is a work of the greatest impor- tance. An illustration of the ingenuity used in adapting them to the accidents of the ground is afforded by the accompanying sections. Sieges are comparatively few in a war as compared with the number of battles and other Fig. 5. BATTERY ON GROUND SLOPING TOWARD THE FORTRESS. (Cross section.) stance of an investment carried to a logical con- elusion. The Confederate army penned up in the city was gradually surrounded and cut off from its source of supplies. The Union army, under General Grant, while closing in on the city, con- structed a line of intrenchments strong enough to resist any possible attack by other Confed- erate troops for the relief of the city. Although Cieneral Grant was gradually pressing his lines forward, the place eventually capitulated as the r^m^^! Fig. 6. battery on ground sloping to either side. (Longitudinal section.) ditions and with different results. In the Russo- Turkish War (q.v. ) Plevna is notable. Geijk Tepe is an instance where the large but poorly disci- plined and poorl.v equipped Turcoman arm,v was besieged and overcome by the smaller but aggres- sive and well-handled Russian armv under Skobe- leff. Allusion has already been made to Jlafe- king and I.adysmith in the South African War. The siege of Fort Wagner, one of the defenses of Charleston. .S. C, by the Union troops was unique in certain respects. Assaults having been made and having failed, recourse was had to ad- vances bv parallels and approaches. The time ar- rived when it seemed impossible to make further headway by this method. Jlining could not be resorted to, since the bottoms of the trenches were already near the level of the ground-water. The proximitv of the forts to deep water en- abled the Union gunboats to add their fire to that of the besieging batteries and so keep down the fire of the fort that the besiegers were able to adance their trenches with great rapidity. In this way the works were carried right up to the fort. The night before the Union troops were to make the second assault the Confederates abandoned the fort, leaving the place by water. The conduct of the siege received the following high encomium from Major Clarke of the English Royal Engineers in his work on fortifications: "The difficulties of the siege, which were consid- erable, were overcome with a skill and readi- ness of resource which the most highly trained force in Europe could not have excelled." Consult: Jlercur, Attack of Fortified Places CSew York, 1894) : Chatham Manual of Military Engineering, part 2, Attack of Fortresses (Lon- don, 1896). See also articles on Siege Gin; Howitzer; T.ctics, Milit.ry: Fortificatiox ; and l''oRTrFicATioNs. Att.c'Iv ..'n Defense of. SIEGE GUN. A piece of artillery used for reducing permanent or semi-permanent works. Siege guns maj' be light or heay, but are more jjowerful weapons, though traveling more slowly, than the field guns. They accompany armies in their field operations, being mounted upon car- riages, which serve for the transportation as well as a support for the pieces while they are being fired. The modern siege cannon adopted for the mili- tary service of the United States are the 5-inch rifle, the 7-inch howitzer, and the 7-inch mortar, all breech-loading. The .5-inch siege rifle weighs 3G60 pounds, is 12.15 feet long, fires a 45-pound projectile with I2V2 pounds of powder, and gives a penetration in steel of 214 inches at 3500 yards. The 7-inch breech-loading rifled siege howitzer weighs 3750 pounds, and fires a projectile of 105 pounds with 10 pounds of powder, giving a pene- tration in steel at 3500 yards of 2.4 inches. The 7-inch rifled siege mortar weighs 1715 pounds, and fires a 125-pound projectile with 5.5 pounds of powder. See Ordnance and Aetilleby.