[4] Numbers quoted from Fischer, Handbuch der Kriegschirurgie, vol. i. p. 22, 1882.
CHAPTER II
MODERN MILITARY RIFLES AND THEIR PROJECTILES IN RELATION TO INJURIES PRODUCED BY THEM ON THE HUMAN BODY
Before proceeding to the actual description of the wounds inflicted by modern military rifles, it is necessary to prefix a few remarks on the mechanism and mode of production of these injuries.
Recent tendency in the construction of military rifles has been in the direction of reduction of bore, and a corresponding one in the calibre of the bullet, the resulting loss of weight in the latter as an element in striking power being compensated for by the attainment of an augmentation of velocity in the flight of the projectile, and a comparatively flat trajectory.
Changes in this direction have endowed the weapons with increase both in range and accuracy of fire; while the greater rapidity with which magazine rifles can be discharged and, in consequence of reduction in weight, the greater number of cartridges which can be carried by each man, also form important factors in the possible deadliness of warfare at the present day. None the less the experience of the present campaign has scarcely justified the early prognostications expressed as to a great increase in the number and severity of wounds amongst the combatants.[5] This comparative immunity is to be explained mainly on two grounds. The increased distance which for the most part separated the two bodies of men, a feature no doubt accentuated by the mode of warfare adopted by the Boer, and his strong sense of the folly of close combat on equal terms, tended to efface one of the chief characters, velocity of flight, on the part of the projectile. The want of effectiveness of the small-calibre bullet as an instrument of serious mischief also kept down the mortality.
Since the year 1889 the calibre of the bullet in our own army has been reduced from that of the Martini-Henry (.450 in.) to one of .309 in. in the Lee-Metford, and a consequent reduction in weight from 480 to 215 grains. To allow of the satisfactory assumption of the more complicated rifling by the more rapidly projected bullet, the lead core has been ensheathed in a mantle of denser metal. The bullet itself is of an original calibre (.309 in.) somewhat exceeding the bore of the rifle barrel (.303 in.), in which way a species of 'choke' is obtained and deep rifling of the surface ensured. Beyond this the comparative transverse and longitudinal measurements and shape have been altered in order to maintain weight, preserve a proper balance during flight, and increase the power of penetration. These alterations with slight differences in detail embody the general principles that underlie the construction of each of the weapons adopted by European nations. It will be well here to consider the influence of each alteration from the point of view of the surgeon.
Calibre.—The effect of the diminution of calibre is (a) to reduce the area of impact of the bullet on the part impinged upon, and hence to lower the degree of resistance offered by the tissues; this to a certain extent tends to neutralise the augmented striking force resulting from the increased velocity of flight. (b) To limit considerably the destructive powers of the bullet, as a smaller area of tissue is exposed to its action. (c) To allow of the production of very 'neat' injuries and the frequent escape of important structures, also the production of remarkably prolonged subcutaneous tracks in positions where such would be regarded as scarcely possible, and in point of fact were impossible with the older and larger projectiles.