skin of those parts which had been subjected to the force of the explosion stained of a deep yellow colour. This yellow stain was regarded as characteristic of the melinite explosive. How far the various chemical powders that have been adopted for ballistic purposes in Continental armies, and that undoubtedly consist of one or other of the violent explosives just described, modified either by chemical combinations or mechanical mixture with other ingredients, will fulfil all the expectations that are held regarding them, will probably only be known after they have been tested by the various trying conditions to which they will be subjected in actual warfare. Compressed atmospheric air.-Compressed air, as it is employed in air-guns for the discharge of projectiles, approximates in its nature and action to the substances which constitute this class of explosives. It is never used for military purposes, and is only noticed briefly here because the shot from such guns are occasionally the cause of wounds in civil practice, though rarely so (see Note 1 in Appendix). As with regular explosives, it is by its sudden alteration in volume when the pressure to which it has been subjected is removed, and by the force derived from its very rapid expansion, that it acts upon the shot which is projected by its agency. It is in this respect that it becomes analogous to one of the solid substances, such as gunpowder, which, by being suddenly converted into vapour or gas, is used as an explosive agent. But from its nature, and from the conditions under which it is ordinarily employed, air-gas can never impart the amount of velocity to a projectile which is necessary for conferring on it sufficient energy to make it of general importance as a source of injury. The wounds which a projectile from an air-gun is able to inflict can only occur within very limited distances from the weapon. CHAPTER III ON THE FIRE-ARMS OR OTHER MACHINES, AND ON THE PROJECTILES CONCERNED IN THE PRODUCTION OF GUNSHOT INJURIES For what reasons, and to what extent, acquaintance with this part of the subject is necessary for military surgeons.A particular knowledge of gunnery does not concern military surgeons, but it is necessary for them to possess an acquaintance with the names and nature of the principal kinds of fire-arms and shot, and some of the peculiarities of their construction. Whatever increases in a marked degree the velocity of movement. force, and range of projectiles, whether it be alterations in the projectiles themselves, or in the fire-arms from which they are discharged, changes proportionably the features of the injuries inflicted by them, and within certain limits, the arrangements which require to be made for the transport, care, and hospitalisation of the wounded in case of the occurrence of war. The military surgeon ought therefore to have some knowledge of the modes of movement, of the rates of velocity and other characteristic features of projectiles, for he cannot have a correct understanding of the nature of the injuries inflicted by them without it. The knowledge further enables a surgeon to recognise and describe more correctly the various kinds of injuries which he meets with in practice; and it is to be remembered army surgeons are required to specify in the tabular and numerical Returns of Wounds, which have to be furnished after engagements, the particular projectiles and weapons by which the wounds have been caused. The student of gunshot injuries requires, further, to know something of the history of the successive changes which have taken place in fire-arms and fire-arm projectiles from time to time, so that he may be able to understand the different descriptions of the injuries produced by them which have been given by surgeons at different periods. It would be difficult for a surgeon whose observations were solely derived from witnessing the effects of the projectiles used in warfare at the present time, to understand some of the observations of the celebrated John Hunter on the subject; neither would many passages in the writings of army surgeons engaged in practice during even so comparatively recent a period as that of the Peninsular War, be clearly understood without the student being acquainted with the qualities of the guns and projectiles by which the wounds were at that time inflicted. But it is only so far as they may be supposed to have exerted an influence on the special features of the wounds caused by them that a knowledge of the changes which have taken place in the construction and arrangements of fire-arms possesses professional interest for military surgeons; and such matters will only be so far noticed in the present work as to meet the requirements which have just been mentioned. General classification of projectiles considered as sources of gunshot injuries. -Gunshot injuries are produced by two classes of projectiles: direct projectiles, those which are projected directly by a primary explosive force; and indirect projectiles, those which are secondarily impelled by projectiles of the former kind, and are subsequently brought into collision with the persons wounded by them. A direct projectile has impressed upon it at first starting a momentum corresponding with the whole of the force by which it has been discharged from the fire-arm, or has been otherwise projected; an indirect projectile has impressed upon it at first starting only so much momentum as the force retained by the direct projectile at the instant of striking is capable of imparting to it, minus the force which has had to be expended in overcoming its inertia or the resistance met with in propelling or rending it from the situation it had been occupying previously to its removal. Of the direct projectiles, some have definite, others indefinite forms. The projectiles which have definite shapes are the several varieties of shot for smooth-bore guns, shell (before explosion), rockets, grape-shot, with the cast-iron balls or sand-shot, and bullets contained in case-shot; together with the various kinds of bullets and shot discharged from machine guns, and portable arms, such as rifles, carbines, and pistols. The direct projectiles of indefinite shape are such as result from the explosion of fougasses, torpedoes, mines, tumbrils, magazines, or from the bursting of any case by the firing of explosive materials enclosed in it, when the case itself has not been previously set in motion by some primary force of impulsion. When shells, discharged in the ordinary way, are burst asunder, the fragments, and the contents of the shell, if any exist, cease to possess purely the characters of direct projectiles, for the primary forces by which they have been projected are to a certain extent modified by the effects of their bursting charges, as will be notified hereafter. The indirect projectiles which give rise to injuries in warfare are very various in their nature: stones or other hard substances struck from parapets, or from the surface of the ground, by gunshot; splinters of iron and wood torn in a similar manner from guns, gun-carriages, platforms, embrasures, timbers of ships, &c.; parts of metal accoutrements, fire-arms, and other articles carried by soldiers; even portions of the bodies of wounded comrades; together with fragments of a variety of miscellaneous objects employed in warfare, or happening to be near to the troops, which have been struck and scattered by shot or shell in the course of their flight. Extraneous substances accompanying projectiles in gunshot wounds. Portions of clothing or other articles worn or carried by wounded persons, or fragments of bones or other parts of the bodies of the wounded men themselves, when they have been detached by projectiles and are forced into parts to which they do not naturally belong, cannot properly be regarded as being projectiles, even of the indirect kind. They do not produce the wounds. Such lodged substances are with more propriety classed among the primary complications of gunshot wounds. Classification of particular projectiles. The projectiles discharged from fire-arms may be most conveniently considered in a surgical work under two groups, viz. : (A.) Large projectiles, discharged from heavy arms of large calibre, such as guns, howitzers, mortars, &c.; or otherwise propelled, as rockets; and (B.) Small projectiles, discharged from machine guns with barrels of small calibre, as the Maxim, Gardner, Gatling, and Nordenfelt guns, or from portable fire-arms, such as rifles, carbines, and pistols. CHAPTER IV LARGE GUNS AND THEIR PROJECTILES Guns. Only a few general remarks are necessary in respect to the guns from which the larger kinds of projectiles are cast, as their shapes and particular mechanical construction have not the same influence on the features of wounds as the like qualities have in smaller kinds of fire-arms. The improvements which have been made in them, as in the smaller kinds of fire-arms, have had for their chief objects increased power of projection, accuracy of aim, and facilities for multiplying the quickness of fire. Guns, or, as they were originally called, bombards, afterwards popularly designated 'cannon,' are the oldest kind of fire-arm. They were originally like mortars in shape, being wider at the mouth than in the bore or at the breech. Guns are stated to have been used in the English army, under Edward III., as early as 1346;8 some writers mention a still earlier date. They appear to have been often cast of immense size, and to have been at first made more with a view of throwing huge stones and battering the buildings of besieged places, than with the intention of inflicting wounds among troops in the open field. The alterations in guns since the early periods just referred to, have gradually given them a more scientific construction; but it is not necessary to follow them through these changes. Guns of enormous weight and dimensions have been constructed of recent years. One of the latest in England has been the 81-ton gun, 27 feet long, with a bore of 16 inches, expending a charge of powder of above 300 lbs., throwing a projectile 1700 lbs. in weight, and striking a blow of 26,300 foot-tons.' But this has been outdone by the 100-ton gun, with its projectile, 2000 lbs. in weight, and a developed striking energy of 31,000 foot-tons. The power of projection attained by gunnery is shown in the instance of a gunshot described by Major Barker, R.A., in a lecture on Modern Gunpowder as a Propellant,' delivered at the Royal United Service Institution, in January 1890. The weight of the projectile alluded to was 380 lbs. It started with a muzzle velocity of 2375 feet per second, rose to a height of 21,263 feet, and had a range of 21,800 yards, or over 12 miles.10 The struggle in these directions does not, however, much concern surgeons; the wholesale ruin and destruction these gigantic weapons are designed for, if accomplished, will leave no scope for surgical help. Moreover, the projectiles used with these monstrous guns are not prepared for acting directly against troops; they are chiefly designed for clearing away obstacles, destroying solid substances, as earthworks, for sinking the ships of invaders; they are not what are sometimes described by artillerists as 'man-killing projectiles,' and if men are killed or wounded by their action, this is only incidental to the accomplishment of their primary purposes. Large projectiles. As regards the projectiles discharged from field-guns, and employed against troops, the surgeon will not fail to notice that the changes which have been successively made in their construction have each increased their power of destructiveness, particularly in respect to the number of wounds. and injuries inflicted by them. Thus, from the imperfectly formed stone or iron round shot of the earliest periods, inventors proceeded to fashion simple shells, which were again followed by the more perfect shrapnell and segment shells and case, each successive improvement in these projectiles being specially designed and contrived for increasing the number of injuries capable of being made by them. The more destructive qualities of the projectiles themselves, together with the increased force of their projection, as well as the increased facilities of rapid fire which have been obtained by the improvement in the guns from which they are discharged, have caused the area of injury as well as the numbers of killed and wounded to be greatly magnified within given periods of time, and have augmented the difficulties of surgical administration, so far as the interests of the wounded are concerned. Although there are few of the large projectiles which were in ordinary use a few years ago that are not now passing away, modern forms being almost wholly confined to cylindro-conoidal shells and cylindrical case-shot, yet a brief description of them is of historical interest, and indeed necessary, for they are constantly referred to in the works of the best writers on military surgery of the present century. Many of them, too, are still to be met with, kept ready for use under certain special circumstances. The projectiles of large size used in warfare have been technically distinguished under the names of shot, shell, carcass, and rockets. Numerous varieties of each of these classes of projectile have been in use, with the exception of the carcass. Examples of the leading varieties only will be noticed. B |