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.
Length.--The comparative increase in length of the bullet is, from the surgical point of view, only of material importance in increasing the weight and therefore the striking power, and in so far as it is a mechanical necessity for the flight of the projectile on an axis parallel to its long diameter, and so tends to ensure impact on the body by the tip of the bullet. This latter is, however, surgically favourable as ensuring a smaller wound.
Weight.--The decrease in weight must be regarded on the whole as altogether to the advantage of the wounded individual, since it cannot be considered to be entirely compensated for by the resulting increased velocity of flight, unless the range of fire is moderately close.
Shape.--The ogival tip and general wedge-like outline, while decreasing the aerial resistance to and increasing the power of penetration possessed by the bullet, at the same time allow the escape of some structures by displacement, while others are saved from complete destruction by undergoing perforation. Beyond this the sharper the tip, the smaller is the area of the body primarily impinged upon, the less the resistance offered to perforation, and to some degree the less the destruction of surrounding tissues.
Increased velocity of flight.--This multiplies the striking force, and compensates in part for decrease in volume and weight of the bullet. It is customary to speak of the velocity as 'initial' and 'remaining.' Initial velocity is the term employed to express the velocity at the time of the escape of the bullet from the barrel; this is also designated as 'muzzle velocity.' 'Remaining velocity' expresses that obtaining during any subsequent portion of the flight of the projectile.
The greatest initial velocity is obtained with the use of bullets of the smallest calibre, but this is not of the practical importance which might be assumed, since the remaining velocity of flight of such projectiles falls more rapidly than that of those of slightly greater mass. Thus, although there may be a difference of a hundred metres per second in initial velocity between two rifles of calibres varying from 6.5 to 8 millimetres (.303-.314 in.), at the end of 1,000 metres the discrepancy is greatly reduced, while at 2,000 metres it hardly exists. Under such circumstances the projectile of greater weight and volume, as possessing the greater striking force, is considerably the more formidable of the two. This is the more important if it be allowed, as I believe to be the case, that velocity per se is of no practical import in the case of wounds of the soft parts of the body, which after all form the preponderating number of all gunshot injuries. The effect of the higher degrees of velocity differs, however, with the amount of resistance met with on the part of the body; hence its serious import is well exemplified when parts of the osseous skeleton are implicated, although even here considerable variations exist, dependent upon the structure of that part of the bone actually involved. The most obvious ill effect of injuries from bullets travelling at high rates is seen in the case of the various parts of the nervous system, and here it is undeniable. High velocity and striking force are also responsible for the prolonged course sometimes taken by bullets through the body.
The actual degree of velocity, as judged by the range of fire at which an injury is received and the resulting injury, is very hard to estimate on account of the many and varying factors which enter into its determination. The mere recital of some of these will suffice to make this evident.
1. Quality of the individual cartridge employed, as to loading, the materials employed, and their condition.
2. The condition of the rifle as to cleanliness, heating, and the state of the grooves of the barrel.
3. The angle of impact of the bullet with the part injured.
4. Resistance dependent on the weight of the whole body of the man struck, or of an isolated limb.
5. Special peculiarities of build in the individual struck, such as thickness and density of the integument and fasciæ, strength and thickness of the bones, &c.
6. State of tension of the muscles, fasciæ, and ligaments at the moment of impact, and fixity or otherwise of the part of the body struck.
7. The degree of wind, temperature, and hygroscopic conditions of the atmosphere.
These form some of the more important points which have to be taken into consideration, in addition to a mere calculation of the actual distance from which a wound has been received from a particular rifle, and taken with the unsatisfactory nature of the evidence as to the latter, which is usually alone obtainable, it is clear that definite assumptions are scarcely possible. In a great number of cases I came to the conclusion that the only indisputable evidence of low velocity was the lodgment of an undeformed bullet. There is little doubt, moreover, that the general tendency of wounded men was to minimise the range of fire at which they were struck, and again that in the majority of cases in this campaign it was quite impossible to determine whence any particular bullet had come, since the enemy was seldom arranged in one line, but rather in several. Again, smokeless powder was generally employed. Beyond this, in some cases where there was no doubt of the short distance from which the bullet was fired, the wounds were due to 'ricochet' of portions of broken-up bullets. The following instance well illustrates this. A sentry fired five times at two men within a distance of six paces, knocking both down. One man received a severe direct fracture of the ilium, the bullet entering between the anterior superior and inferior iliac spines and emerging at the upper part of the buttock. The entry and exit apertures were large but hardly 'explosive,' as a subcutaneous track four to five inches long separated them. Besides this both men had other lesser injuries; thus in the second two perforating wounds of the arm existed. The latter were not unlike type Lee-Metford wounds, and were regarded as such until a few days afterwards when a hard body was felt in the distal portion of one track and removed. This proved to be a part of the leaden core only, and the similar wound had no doubt been produced by a like fragment, the bullet having broken up on striking the stony ground.
Trajectory.--The comparative flatness of this depends on the construction of the rifle and the propulsive force employed, and varies as does velocity with the nature, excellence, and amount of the explosive, the correctness of the principles upon which the bullet is devised, and the mechanical perfection of its manufacture. Its importance naturally consists in the manner in which it affects the possibility of covering objects on a wide area of ground and thus creating a broad 'dangerous zone.' A bullet fired on level ground from any one of three of the rifles referred to later (Lee-Metford, Mauser, Krag-Jörgensen), sighted to 500 yards and fired from the shoulder in the standing position, will cover some part of an erect man of average height during the whole extent of its flight. A body of men within that distance is therefore in a position of extreme peril in the face of a good shooting enemy.
The importance of a flat trajectory is progressively lost, however, with any rifle, as the weapon is gradually sighted to greater distances. Thus when sighted to 2,000 yards the bullet from the Lee-Metford rifle rises 174 feet, and a whole army might comfortably be situated over a considerable area within that distance. The importance of flatness of trajectory is also influenced by the nature of the ground occupied by the combatants. Thus when the area to be covered consists in ground first rising then falling from the rifleman, the trajectory will become more or less parallel to the surface crossed, and the 'dangerous zone' will be correspondingly increased in extent. On the other hand, when the ground slopes away from the rifleman the rise of the projectile is exaggerated, and reaches its most limited capacity of covering an intervening space when the flight crosses a hollow.
Revolution of the bullet.--It only remains in this place to say a few words concerning the revolution imparted to the bullet by the rifling of the barrel. This ensures the flight of the projectile on a line parallel to its long axis, and notably increases its power of penetration.
Both these properties of the flight are to the advantage of the wounded, since, as already mentioned, the more exactly the impact corresponds to a right angle with the skin, the more limited will be the area of contusion, even if it be of the most severe character, while to the twist of the bullet must be ascribed a not inconsiderable part in the explanation of the ready and neat perforations of narrow structures which are frequently produced.
It has been pointed out that the Lee-Metford bullet turns on its own axis once in a distance of ten inches, while the Mauser revolves once in a distance of eight and eleven-sixteenths inches; hence not more than at most two revolutions are made in tracks crossing the trunk, and not more than half a full revolution in the perforation of a limb. None the less, no one can deny the influence of the one half turn of supination in entering a perforating tool of any description, both as preventing splintering, and in preserving the surrounding parts from damage.
Beyond this, the spiral turn of the bullet, by diverting a part of the transmitted vibrations into a second direction, must, in the case of wounds of the body, help to throw off contiguous structures, and while those that are in actual contact are more severely contused, the surrounding ones suffer somewhat less direct injury. It must be borne in mind, also, that rapidity of revolution does not fall pari passu with that of velocity of flight, but that the former undergoes a comparatively slighter diminution until the bullet is actually spent. Hence, the influence of revolution is felt, however low the velocity may be, provided sufficient striking force is retained to enter the body. A word must be added here as to the surface of a discharged bullet; this, in taking the rifling of the barrel, becomes permanently grooved. The depth of the groove differs with the variety of rifle. In the Lee-Metford the grooves are deep (.009), in the Mauser slightly less so (.007), but the surface of both bullets is comparatively roughened when revolving in the body, and this circumstance, since the projectile exactly fits its track, may influence the degree of the surface destruction of tissue, and somewhat aid in the clean perforation of bone, since a little bone dust is always found at the entrance aperture of a canal in cancellous bone.
During the campaign many varieties of rifle projecting bullets of widely differing calibre were employed by the Boers, many of whom as sportsmen preferred the rifle to which they were accustomed to a regulation weapon, and an illustration of a large variety of bullets from cartridges which I collected from arsenals and camps is given below (p. 96). The great majority of the men, however, were armed with small-calibre weapons of some sort, and as the wounds produced by these are of chief interest at the present day, I shall say little of any others, beyond an occasional reference to Martini-Henry rifle wounds which may be considered to represent approximately those made by large leaden sporting bullets.
[Illustration: FIG. 14.--Type Cartridges in common use during the war. From left to right: Martini-Henry, Guedes, Lee-Metford, (Spanish) Mauser, Krag-Jörgensen]
The most important, as the most frequently employed, rifles projecting small-calibre bullets were the Krag-Jörgensen, Mauser, Lee-Metford, and Guedes, given in the order of increase of calibre (from 6.5 to 8 millimetres, or .254-.314 in.) in the bullets. As to the seriousness of wounds produced by these there is little to choose, differences in character being only those of degree. Such differences depended on the area of tissue implicated, corresponding with the calibre of the particular bullet, the comparative weight of the bullet, and the degree of velocity of flight maintained at the moment of impact. When, however, any of these bullets have been exposed in their flight to influences capable of causing deformity of their outline and symmetry, peculiarities of construction and in the composition of the metals employed in their manufacture may materially alter the character of the wounds produced and revolutionise a classification founded purely on the relative weight, calibre, and degree of velocity with which each is endowed.
TABLE I
Some particulars of the four rifles and their projectiles are collated in Table I., to which is added the corresponding information regarding the Martini-Henry for the purposes of comparison.
TABLE II.--PENETRATION
The penetration of the Martini-Henry and the Lee-Metford or Lee-Enfield rifle with Mark II. bullet is as follows:
Martini-Henry 15-1/2 in. of 1 in. deal boards 19 in. of sand 1 in. apart containing 15 per cent. of moisture
Lee-Metford {Mark II.} 42 in. of 1 in. deal boards 60 in. of sand Lee-Enfield {bullet } 1 in. apart containing 15 per cent. of moisture
The penetration of bullets of .314 calibre differs little from that possessed by the Lee-Metford or Lee-Enfield, of which the muzzle velocities are very little lower, with Mark II. bullet. The Belgian Mauser perforates 55 inches of fir-wood at 12 metres distance. With regard to the penetration of bullets of smaller calibre that of the Roumanian Mannlicher (.256) may be taken as typical. When fired into a sand butt at 25 yards the bullet enters 9 inches and then breaks up.
The comparative size of the different cartridges is shown in fig. 14.
The general remarks already made as to the effect of weight, calibre, and velocity sufficiently explain the importance of the particulars given in this table, but it will be noted that the Lee-Metford rifle is inferior to both the Krag-Jörgensen and Mauser rifles in the initial velocity transmitted to its bullet. The tendency to equalisation, in this particular, when the remaining velocity is considered, has been mentioned; but it may be of interest if I quote from Nimier and Laval[7] the scale on which the decrease in velocity takes place in the case of the three weapons.
METRES PER SECOND
Giving full importance to the effects of velocity as a factor in the severity of the injuries produced, when the large proportion of wounds received at distances above 1,000 yards is borne in mind, we see how rapidly the superiority of the smaller projectiles is lost. This loss, even in the early stages, is probably more than made up for in the case of the Lee-Metford, when the superiority in weight, calibre, and bluntness of extremity as contributing to striking force is taken into consideration.
The striking force (kinetic energy) of a bullet is indicated by the following formula: F = 1/2 mv.^{2}; that is to say, the striking force is equal to half the weight of the bullet multiplied by the square of the velocity.
In point of fact, with unaltered regulation bullets I was never able to determine any very material difference between the wounds produced, further than that the wounds of entry and exit in the soft parts tended to correspond with the calibre of the particular bullet concerned. Although the immense majority of the wounds which came under my notice were caused by the Mauser bullet, yet I saw some hundreds of wounded Boers and a good many of our own men wounded by Lee-Metford bullets, in the latter case no doubt by some of the sporting varieties. The only cases that I can call to mind or have noted as exhibiting a superior wounding power in the Lee-Metford bullet are some injuries to bone. Thus I saw a considerable number of clean perforations of the patella produced by Mauser bullets, while the only two Boers whom I saw with injured patellæ had suffered transverse fractures. Again, I have a lively recollection of an old Boer who had suffered a fracture of the middle third of the femur, in the thigh of whom, with small apertures of entry and exit, a cavity of destroyed tissue, five inches across, was found beneath the fascia lata at the distal side of the fracture. I cannot however say that I did not observe many equally severe injuries to the femur produced by Mauser bullets in our own men, and as far as fractures of the skull went, a somewhat crucial test, among the men brought off the battlefield alive, I never saw any difference in severity whatever.
[Illustration: FIG. 15.--Sections of four Bullets to show relative shape and thickness of mantles.
From left to right: 1. Guedes; regular dome-shaped tip; mild steel mantle; thickness at tip 0.8 mm.; at sides of body 0.3 mm. 2. Lee-Metford; ogival tip; cupro-nickel mantle; thickness at tip 0.8 mm.; gradual decrease at sides to 0.4 mm. 3. Mauser; pointed dome tip, steel mantle plated with copper alloy; thickness at tip 0.8 mm.; gradual decrease at sides to 0.4 mm. 4. Krag-Jörgensen; ogival tip as in Lee-Metford; steel mantle plated with cupro-nickel; thickness at tip 0.6 mm.; gradual decrease at sides to 0.4 mm. The measurements of the sides are taken 2.5 cm. from the tip. Note the more gradual thinning in the Lee-Metford mantle.]
These points of comparison having been made, it only remains to consider one other point, that of the relative stability of the bullets. This is a matter of the greatest importance as regards the regularity or otherwise of the wounding power of the projectile, and, as far as my experience went, I believe the Mauser to far exceed the Lee-Metford in instability of structure.
The core of all four bullets is composed of lead hardened by a certain admixture of tin or antimony, but the mantle differs in composition, thickness both general and in different parts of the bullet, mode of fixation, and consequently in its power of resistance to violence.
Fig. 15 gives an exact representation of the relative thickness of the mantles, and shows the general tendency to a thickening of the mantle at its upper extremity, designed to increase both the stability and striking power of the projectile. It will be noted that in general stoutness the Lee-Metford stands first, as the case increases gradually in thickness from base to apex.
Beyond this it must be noted that the Lee-Metford is the only one of the four that is ensheathed with a mantle composed of a definite alloy, this consisting of 80 parts of nickel and 20 of copper. Two of the remaining bullets, the Mauser and Krag-Jörgensen, are ensheathed with steel covered with a thin coating of an alloy of copper or cupro-nickel, to take the rifling of the barrel, while the third has a plain steel mantle which is covered with a layer of wax to take the place of the nickel used in the manufacture of the two others. It is interesting to mention here that the Boers evidently found the copper alloy coating insufficient for its purpose, or at any rate not satisfactory in preserving the weapon from the ill-effects consequent on the friction between the steel case and the rifling of the barrel, as at about the middle of the campaign they began to use their bullets waxed, as in the case of the Austrian Mannlicher; hence the legend of the poisoned bullets which caused such a sensation for a short period amongst the uninitiated. It is possible also that the additional layer of wax was necessitated by the wearing of the barrel.
The wax employed for the Mauser bullets was not originally green. Mr. Leslie B. Taylor informs me that it is probably paraffin wax, the green colour depending on the formation of verdigris from the copper alloy with which the steel envelopes are plated. This completely corresponds with my own experience, since on the bullets in my possession the green colour, originally pale, has steadily increased in depth. Many old leaden bullets I found in the Boer arsenals were also waxed, but in this case no alteration in colour had taken place. The Guedes bullets, which are cased in mild steel, become somewhat brown with exposure from a similar oxidation or rusting of the surface.
As far as my experience went, however, the steel casing has an important surgical bearing beyond the mere question of wear and tear on the rifle barrel. That it possesses elasticity and capability of bending is obvious, and in a later chapter, devoted to irregular wounds, several illustrations of such deformities are given; but when it strikes stone I believe it splits and tears with very much greater freedom than the cupro-nickel mantle of the Lee-Metford. At any rate, I never came across Lee-Metford bullets deformed to the same degree as Mauser bullets, either when removed from the body, or as ricochet projectiles on the field of battle. For this reason, therefore, provided the fighting takes place on stony ground, I believe the Mauser bullet and others ensheathed in steel to be much more dangerous surgically than those encased in cupro-nickel. I fancy this would be equally the case even if the mantles were of exactly the same thickness.
The layer of copper alloy on the steel mantles is also a physical characteristic worthy of mention. This very readily chips off in a manner similar to that we are accustomed to see with nickel-plated instruments. This may be due to the compression into the grooving of the rifle, or as the result of passing impact of the bullet with an obstacle previous to entering the body or contact with a bone within it. Small scales of metal set free in one of these ways are seen in a very large proportion of Mauser wounds, and although they are so small as usually to be of little importance, the presence of such in, for instance, the substance of one of the peripheral nerves which has been perforated cannot be considered a desirable complication.
To recapitulate, it would appear that at mean ranges, both in striking force and as regards the area of the tissues affected, the Lee-Metford is a superior projectile to the Mauser, in spite of the greater initial velocity possessed by the latter. On the other hand the comparative ease with which the Mauser bullet undergoes deformation either without or within the body, so ensuring more extensive injury and laceration, renders it the less desirable bullet to receive a wound from when not in its normal shape and condition.
I can say little about the remaining two rifles. The Krag-Jörgensen was little used, and beyond pointing out its capacity to inflict very neat individual injuries, in which it must surpass even the Mauser, I can only add that I had no opportunity of forming an opinion as to the danger dependent on the great initial velocity imparted to the bullet. The Guedes rifle has been included in the table because it approximates in bore to the other three. Its bullet is of the same calibre as the Austrian Mannlicher, one of the most powerful military rifles in use, and it was used to a considerable extent during the war by the Boers.[8] As to its capabilities, it appeared an inferior weapon, since want of velocity and striking power of the bullets was indicated by the number of these which were retained in the body, and by the fact that I never saw one extracted that had undergone any more serious deformation than some flattening on one side of the tip. On the other hand wounds of the soft parts occasioned by it were only to be distinguished from Mauser wounds by their slightly greater size, and at a short range of fire the weight and volume of the bullet made it a dangerous projectile.
The question of deformed bullets will be again referred to at length in the section on wounds of irregular type, and a number of type specimens are there figured and described (p. 76). In the same chapter will be found illustrations of a number of sporting bullets of small calibre, as well as of large calibres in lead, found in the Boer arsenals and camps. I have placed them in that position as mainly of interest in connection with the occurrence of large and irregular wounds (see figs. 42 and 43, pp. 95 and 98).
The small sporting bullets were mostly of the Mauser (.276), Lee-Metford (.303), or Mannlicher (.315) calibre.
FOOTNOTES:
[5] See tables, pp. 12, 13, 15, Chapter I.
[6] The weights are from cartridges brought home. The charge of powder was small and variable.
[7] H. Nimier and E. Laval, Les Projectiles des Armes de Guerre, p. 20. F. Alcan. 1899.
[8] Mr. Leslie B. Taylor informs me that this rifle is a discarded Portuguese regulation pattern, with which a copper-ensheathed soft-nosed bullet was originally employed. For the purposes of the present campaign a modified cartridge was constructed. Examination of some specimens in my possession showed the charge of powder to be very small
