Few subjects of equal interest and weight have been more neglected, or perhaps, which is worse, more loosely and vaguely treated, than the medical statistics of armies, rich in facts, and promising, both in a political and scientific point of view, valuable results; it is a matter which has been left principally to the adjutant and serjeant-major, referring chiefly to the ranks absent or present; to some hospital returns in which numbers still are the object, but rarely or never combined in such order and system as to furnish all the data necessary to the development of certain important averages and general principles. And how should they? since but little labour seems to have been bestowed to define what are the general results, the conclusions, and the principles which it is desirable to establish upon an unerring basis. These, it seems to us, are First-The causes affecting the health and lives of soldiers, classed in their relative value, as to frequency and fatality. Secondly-These causes once clearly ascertained, defined, and classed, their mode of action, the precise degree and duration of their effects, would form the next subject of inquiry. Thirdly-The various means of preventing, modifying, or controlling all injurious influences divided into-measures emanating from the commander-in-chief, and measures under the immediate coutrol of the medical staff-such as medicinal treatment, &c. From such a series of data-independent of the first great advantage of passing regulations and taking measures best calculated to insure the least possible loss and suffering-would flow one of great political importance -viz. the power of anticipating the general results of warlike operations, and consequently determining the measures necessary to meet the waste of men -diminution of effective strength, hospital stores, &c. Many returns have been published at different periods, but neither any one set, nor all put together will give the facts necessary, and for a simple reason; the true aim and objects of medical statistics, as applied to armies or fleets, have never been sufficiently well ascertained or clearly defined. Precise and abundant information bearing upon and elucidating certain points, can never be collected while those points are either not held in view or vaguely perceived. Sir George remarks on this subject, that "Some interesting and valuable statistical information upon this subject has lately been given to the public by Mr. Edmonds, and by Mr. Alcock, in his Notes on the Medical History and Statistics of the British Legion in Spain.' Some of the more important points on which his tables bear, are the ultimate loss to the effective strength of an army from wounds, and the scale, in which the first loss after an action progressively diminishes; the average mortality from musket wounds; the proportion which the different classes of wounds bear to each other; and this with reference to the wounded of a force attacking and defending batteries, houses, and lines, skirmishes and actions in the open field, and the assault of a fortified town." 63. Neither of these gentlemen, however, has fulfilled all the indications, and it remains for those engaged in the next war to furnish the data so much required. They must first begin by defining all the principal points to be elucidated, for it is to the want of previously formed and clear conception of the whole scope and aim of the inquiry, that Mr. Alcock seems justly to attribute his being enabled only partially to carry out his views on this subject, by the facts he collected while with the armies of Spain and Portugal. From the imperfect return already in existence, Mr. Alcock seems to have demonstrated two or three conclusions not hitherto generally receivedconclusions and averages calculated to influence the operations and success of a war. Thus "The period of smallest loss to an army is a victorious and vigorously prosecuted campaign, with frequent battles and much marching." 63. That an inclement Winter, ushered in by a wet Autumn, passed by troops in quiet cantonments, is the most destructive period. That the heat of Summer is as injurious as the rains or the cold of the succeeding seasons, causing as much sickness and mortality. Hence, in an active and successful campaign, different seasons produce nearly similar results. To follow out the subject beyond these indications of the value and importance of the information wanted, would lead us much too far. On hospital arrangements and the transport of wounded, the author has given some excellent observations in reference to two points of military organization, in which we are far inferior to some other armies, and notably to the French. The formation of an ambulance for the transport and immediate treatment of wounded, and an hospital corps for the due and efficient attendance on the sick in hospitals, &c. are indispensably necessary. thing can be more defective or pregnant with evil to the service, than the present regulations-injurious alike to the healthy and the non-effective. Sir George truly remarks No "For this purpose, the only effectual provision seems to be, the formation of an Hospital corps, placed entirely at the disposal of the medical staff, and consisting of men either enlisted and embodied solely with this view, or transferred to the hospital establishment in consequence of having, from years or from accidents, become less effective in the line. A body of men of this description, trained to the particular duties required of them, qualified to attend the sick in the hospitals, as well as to succour and bear off the wounded in the field, would preserve the integrity and effective force of regiments; would afford a degree of comfort to the sick and wounded, to which they are too often strangers; and would give an efficiency to the medical staff, which the most zealous devotion to the duties of the service cannot otherwise ensure." 88. This experiment was fully tried, it seems, in the Legion, and with the happiest results. Our means of transport for the wounded are very ill adapted and arranged, and certainly call for no little reform. We have understood that, on these two heads, some measures were in contemplation by the government, at which we sincerely rejoice, for much are they required. A large portion of the work-devoted to the consideration of wounds in all the variety of nature and circumstance attendant on a soldier's injuriescontains a clear and well-arranged digest of the present state of our knowledge on military surgery, with many original and interesting remarks and suggestions. With some surprize we observe a practice we had long thought abandoned, together with the charms and wonder-working salves of the dark ages, described as still prevalent in the French army. No. LX. FF "It would appear that this practice of indiscriminate dilatation is not yet abandoned by the French surgeons, for Mr. Alcock in a letter to me, states, that upon a very recent occasion, after the assault of Irun, a military ambulance was dispatched from Bayonne with offers of assistance to the wounded; and that all the Spanish who fell into their hands were unmercifully estrellated by the French bistoury. To this general rule there is, however, at least one creditable exception. M. Baudens, chief surgeon to the French troops serving at Algiers, seems to have had his eyes opened to the mischievous effects of this exclusive rule; and his conversion seems to me a point of much interest and importance." 216. We may remark, en passant, that we were struck by the poverty of the leçons given by Dupuytren, on the gun-shot wounds resulting from the days of July, 1830, the first time the printed account of them met our eyes. They seem to be a pas en arrière to Larrey, instead of being, as was naturally to be expected, something in advance. The torsion of arteries, now nearly totally relinquished, seems to have been extensively tried within the last few years. "Torsion has been said to act less certainly on the smaller than on largersized arteries, and hence, perhaps, the little progress it has made in this country. Mr. Alcock tells me that torsion was tried in fourteen consecutive amputations, at Oporto, including one at the shoulder-joint, and that secondary hæmorrhage occurred only in one of them." 231. As an outline of lectures forming a clear and tolerably concise digest of the principal subjects within the scope of military surgery, and of most importance to the young surgeon about to enter on such a career, it is an excellent work, and much care and labour in condensing old matter and adding new, has evidently been bestowed upon this edition, with great advantage to the reader. ON THE FUNCTIONS AND DISEASES OF THE EAR. I. THE CYCLOPEDIA OF ANATOMY AND PHYSIOLOGY. Edited by Robert B. Todd, M.D. F.R.S. &c. &c. Part XV. London, January, 1839. Price five shillings. II. A TREATISE ON THE STRUCTURE, ECONOMY, AND DISEASES OF THE EAR; BEING THE ESSAY FOR WHICH THE FOTHERGILLIAN GOLD MEDAL WAS AWARDED BY THE MEDICAL SOCIETY OF LONDON. By George Pilcher, Lecturer on Anatomy and Surgery at the Theatre of Anatomy and Medicine, Webbstreet, Borough; and Senior Surgeon to the Surrey Dispensary. London, 1838, pp. 324. I. THE FUNCTIONS OF THE EAR. THE appearance of the present Part of the Cyclopædia of Anatomy has been materially delayed, but the editor promises the publication of the next part in a month, and the completion of the work as early as possible. The best way, we fancy, for the public to get the work rapidly concluded, is to patronize it. The Part before us contains Hearing, Organ of, concluded, by T. Wharton Jones, Esq. Hearing, by Dr. Todd. Heart, Normal Anatomy, by Dr. J. Reid. Heart, on the Arrangement of the Fibres of the, by H. Searle, Esq. Heat, Animal, by Dr. Edwards. We can speak in very favourable terms of the execution of all the articles. The work is really a very valuable one, and deserves encouragement from the scientific part of the profession-more than, we fear, it gets. Yet other works, of inferior merit, have received more. If individuals cannot afford to purchase it, all medical libraries and book societies should have it. We shall select the article Hearing, by Dr. Todd, for an analytical notice. We do so, not because it is better than the others, but because the majority of medical men know little of the physiology of the ear, as most that has been learnt on the subject is of recent date. We need not dilate on the importance of hearing. But a few words on sound may not be misapplied. Sound is the result of an impulse of any kind made on the organ of hearing. Usually, the impulse is conveyed by the air. The body by which the sound is produced, denominated by Professor Wheatstone a phonic, occasions in the surrounding air vibrations or oscillations, corresponding in number and extent to those which exist in itself; and these vibrations or oscillations being propagated to the organ of hearing, give rise to the sensation. It would be idle to multiply instances of this. The sound of a cannon fired is as good as any. But the sound may be communicated directly through the bones of the cranium, or it may arise from direct contact of a solid with the tympanum. Every body who has had a tooth drawn must have been struck with the sound occasioned by the extraction; and the beating of the carotids in cases of nervousness or of cardiac hypertrophy, is a familiar instance of the sound conveyed by the solid structure of the cranium. A fine probe introduced carefully through the meatus externus, and made to impinge upon the membrana tympani, however gently, will occasion the sensation of sound. Any irregular impulse communicated to the air produces a noise, in contradistinction to a musical sound. This latter results from a succession of impulses, which occur at exactly equal intervals of time, and which are exactly similar in duration and intensity. When these impulses succeed each other with great rapidity, the sound appears continuous, in consequence of the duration of the impression upon the auditory nerve. The frequency of repetition necessary for the production of a continued sound from single impulses is, according to Sir J. Herschel, probably not less than sixteen times in a second, though the limit would appear to differ in different ears. In this respect hearing is analogous to sight. A rapid succession of images upon the retina produces the idea of uninterrupted colour or light. The schoolboy's amusement of twirling a burning stick in the air is a common example of this. We distinguish in musical sounds, 1, the pitch; 2, the intensity or loud ness; 3, the quality. The pitch of the sound depends on the rapidity with which the vibrations succeed each other, and any two sounds produced by the same number of vibrations or impulses in the same time are said to be in unison. The loudness or intensity depends upon the violence and extent of the primitive impulse. The quality is supposed by Sir J. Herschel to depend on the greater or less abruptness of the impulses, or generally, on the law which regulates the excursions of the molecules of air originally set in motion. Different media convey sound with different rates of velocity. In air at the temperature of 62° Fahr. sound travels at the rate of 1125 feet in a second, or 1090 feet in a second in dry air at the freezing temperature. This velocity is independent of the pitch and quality of sound. Distance does not destroy the harmony of a rapid piece of music played by a band. Biot caused several tunes to be played on a flute at the end of a pipe 3120 feet long, and found that they could be distinctly heard without the slightest derangement. "Neither is the velocity of sound affected by an increase of density in the air. It is, however, greater in warm than in cold air in consequence of the greater elasticity of the former. In the different gases much variety has been observed in the velocity of sound; through carbonic gas the rate of the velocity is said to be one-third slower than ordinary, but through hydrogen gas, which is twelve times more elastic than common air, the speed exceeds the usual rate three and a half times. A more striking difference is as regards the intensity of sound or the impression it is capable of producing on our organs of hearing. This varies considerably with the increase or diminution in the density of the transmitting gas. By means of a piece of clock-work, which caused a hammer to strike at regular intervals, the conducting power of the gas could be estimated, the clockwork being placed in a glass receiver filled with the gas. It was thus that Priestly ascertained that in hydrogen the sound was scarcely louder than in vacuo; in carbonic acid and in oxygen it was somewhat louder than in air.” 566. Water can transmit sound, or we may well suppose that God would not have given ears to fish. M. Colladon, by means of a tin cylinder three yards long, and eight inches in diameter, closed at its lower end but open to the air above, plunged vertically in the water, was enabled to hear the sound of a bell at the distance of about nine miles, and from numerous observations he concluded that the velocity of sound in water at about 46° Fahr. was equal to 4708 feet in the second. Solids are still better conductors of sound, and those which are homogeneous, hard, and elastic, are the best. A conclusive experiment, by Herhold and Rahn, is related by Chladni :—a metallic wire 600 feet long was stretched horizontally, and at one end a plate of sonorous metal was attached; when the plate was slightly struck, a person at the opposite end, holding the wire in his teeth, heard at every blow two distinct sounds, the first transmitted almost simultaneously by the metal, the other arriving later through the air. Biot, with the assistance of Messrs. Boulard and Malus, concluded the velocity of sound in cast iron at the temperature 51° Fahr. to be 11,090 feet in a second. Sound, like light, admits of reflexion, the angle of which equals the angle of incidence. Echos are such reflexions, and, the sound being reflected once or oftener, the echo is correspondingly single or repeated. |