Percussion shell, on account of its very sensitive fuze, bursts on penetrating the shield, while percussion shrapnel goes entirely through the shield and bursts about ¹⁄₂ m. in rear of it. [Illustration: Percussion Shell, Model ’96.] Targets located immediately in rear of parapets or under light splinter proofs may be reached with time shell burst directly over or close in front of them. The depth of the beaten zone of this projectile is small, seldom exceeding 50 m., even when the fire is directed against targets in the open. About 75% of all the fragments are capable of inflicting disabling wounds when the interval of burst is short. The peculiar character of the projectile necessitates a very careful adjustment in range and in height of burst. The French _obus allongé_, a high explosive percussion shell (melinite charge; angle of the cone of dispersion exceeds 100 degrees) is employed only for the destruction of material objects.[111] [111] When firing on animate objects, the beaten zone of this projectile does not exceed a space 50 m. wide and 20 m. deep, but the concussion of the explosion will undoubtedly be felt at a greater distance. The explosive effect of the projectile is equivalent to that of 30 kg. of powder. The explosion of the projectile produces a cone-shaped crater having a diameter of 2 and a depth of 0.50 m. Ten melinite shells per running meter are required to destroy a parapet 3 m. thick and 2.30 m. high. The French projectile, on account of the fuze used, bursts only after it has pierced thin walls or shields. [Illustration: Time Shell, Model ’96.] 2. THE LIGHT FIELD HOWITZER. The realization that the power of resistance of a defender lodged in deep trenches, could not be broken by the fire of guns having a flat trajectory, led to the re-adoption of a gun capable of high angle fire, which had been eliminated from the field artillery upon the advent of rifled cannon.[112] [112] After March, 1859, the artillery of a mobilized Prussian army corps consisted of three horse batteries, each armed with six 6-pounder guns and two 7-pounder howitzers; six foot batteries, each armed with eight 12-pounder guns; and three foot batteries, each armed with eight 7-pounder howitzers. Thus the artillery of an army corps numbered 30 howitzers and 66 guns. For both flat trajectory and high angle fire, the light field howitzer, model ’98, employs shrapnel weighing 12.8 kg. (500 jacketed bullets, @ 10 g.; time fuze graduated from 300 to 5600 m.) and shell weighing 15.7 kg. (0.37 kg. explosive charge, model ’88; time fuze graduated from 500 to 5600 m.). As delay action fuzes are used, it is possible to utilize to the fullest extent the power of penetration of the projectile before it bursts.