country,* can compare in its effect upon the practice of surgery, with the introduction of the ligature into use as now employed. This admirable instrument, it is true, controlled the hemorrhage perfectly, and enabled surgeons to perform an infinite number of bold operations from which they would have shrunk without it. But effectual as it is in certain cases, it is utterly inapplicable in a very great variety of circumstances, and simple pressure with the finger, (a practice founded upon accurate knowledge of the physiology of the circulation,) which was at first called in to take the place of the tourniquet in situations where this instrument was not applicable, has, with many persons, quite supplanted it, and with all proved itself, under many circumstances, an adequate substitute. Not so with the ligature. It has commended itself more and more to the notice of surgeons and has taken its place, like vaccine, on the list of those indispensablethose never-to-be forgotten improvements which seem destined to last forever. In speaking thus of the introduction of ligatures into practice, it must be understood that I do not mean to make allusion to the time when they were first applied. This period is, to say the least, uncertain. It is probable that, in some way or other, they were used at a very early day. But if we are to take the passages cited from very old authors as satisfactory proof that ligatures were applied upon divided arteries or veins, how shall we account for the other and barbarous resorts to which they had recourse for averting the dangers of hemorrhage? Why did Abu'l Kasem introduce that frightful practice, at the mention of which, even now, our blood runs cold, of amputating with a red hot knife? Why was it that from Hippocrates to Celsus, amputations were only performed for mortification of a limb, and the operation done in the dead part? And why was it that even after Celsus had laid down better rules, succeeding surgeons, still having the fear of hemorrhage before their eyes, relapsed again to the old habit of cutting in the dead parts, thus carrying surgery many centuries backwards? Why, in the 15th century, after the invention of gunpowder, were so manymany victims suffered to perish miserably with their fractured bones and lacerated flesh mortifying and suppurating, and their sufferings made a thousand times more insufferable, and their fate a thousand times more inevitable, by the inflammatory drugs and burning irons, with which their festering sores were made to fester worse, if it were not that the dread of amputation kept the surgeon at bay, because he knew of no means of arresting the hemorrhage that would ensue, except such as were even more fearful than the frightful dangers which were already star * Dr. Moore of Massachusetts. See Cooper Surg. Dict., Art. Tourniquet. ing him in the face-plunging the stump into boiling pitch, for instance, as practiced by the Arabians.* Surgery was, at this time, and had for several centuries before, it is true, been in a state of fearful darkness. It had receded many long steps from the point at which even Celsus had placed it. But it is evident that if the application of ligatures, as they are now used, had been known, gun-shot wounds would have been differently treated. Soon after the period to which I am referring, several illustrious names are found on the list of surgical reformers. Of all these none stands so prominent as Ambrose Paré. A long and brilliant career has placed him in the front rank of those who stand highest in the estimation of posterity. Among his greatest achievements are the improvements he made in the treatment of wounds. But my present purpose leads me no further than to call attention to the remarkable directions he gives in the †22d ch. of his 10th Book, for seizing and tying all the bleeding vessels after a limb has been amputated. From this time the ligature may be said to have been regularly introduced into surgery not to be again displaced. For soon after came Harvey's description of the circulation, and the anatomy of the arterial system became better known. Clearer views of physiology and pathology have served to enlarge the sphere of its usefulness, and now it is employed for other and equally important purposes. Its potent agency in the treatment of a variety of diseases, principally those of the arterial and venous systems, has made it the subject of numerous experiments, undertaken with a view to the improvement of the various processes employed. The foregoing remarks are intended as introductory to a few observations on the substances best adapted for making ligatures. But before entering into the subject, it may be well to refer in as few words as possible, to the structure of the parts concerned. Arteries have three distinct coats, independent of the sheath of condensed cellular tissue in which those of the larger size are enclosed. The external coat is tough and resisting, in texture resembling, somewhat, that of the sheath, being like that composed of condensed cellular tissue. Its fibres are not arranged in regular layers and in parallel directions as are those of the coat next to be mentioned, but have an arrangement which has been likened to the fibres of cotton pressed together. Its toughness and powers of resistance are such that it is capable of withstanding the action of the smallest sized thread used as a ligature, even when this is drawn with great force. Vessels exist in this *Cooper Surg: Dic., Art. Surgery. Ev. Comp. par J. F. Malgaigne. Paris. 1840. tissue which reach it from the cellular sheath surrounding the vessel. The second or middle coat is entirely different both in texture and properties. It is composed of fibres probably of a peculiar substance,* (but which substance has been considered as muscular by many,) which are arranged in the most regular manner surrounding the calibre of the artery more or less completely in proportion as they are more or less superficial. The superficial or external layer is attached to the inner surface of the coat just described, by the middle part of its fibres, and these fibres which are the longest of all, pass about two-thirds of the way around the artery. Those in the next layer are shorter, and so on for the rest the inner layer being the shortest of all. The manner in which these fibres are all attached to the inner coat of the artery is, according to Manec, as follows, viz: At a short distance from their termination they bend inwards, those of the outer layers passing between those of the inner layers so that all of them except those of the external layer, are enabled to reach the internal coat upon which they fix themselves. The internal layer of all, he says, is attached somewhat differently; they change their direction so as to become longitudinal instead of transverse, as they were originally, and in bending take different directions so as to interlace each other, by which means a certain degree of force is acquired, enabling this layer to offer rather more resistance to longitudinal traction or wedge-like pressure, such as that made by a small ligature. Bichat describes the mode of attachment differently. He says it is very slight, and has some analogy to the manner in which organic muscular fibres attach themselves to the sub-mucous tissue.† Beclard says these fibres are more crowded together in the inner and less so in the outer layers, to which circumstance he attributes the greater power of resistance of this layer. He says "it is difficult to determine the direction of the fibres; the transverse is the only evident and is, therefore, that of the greatest number. Many authors-Mascagni, Hunter, Sommering-say that they form spirals, or at least that they are rather oblique than directly circular."‡ Whether Beclard or Manec be correct, I cannot undertake to decide positively, but am disposed to side with the latter from the result of a simple experiment, viz: take a portion of an artery and apply the ligature around it as usual; then lay open another portion longitudinally and fold it, so that the ligature when drawn will act at right angles to the direction of the fibres * Bichat Anat. Gen. vol. 2, p. 54, and note by Blandin. † Anat. Gen. vol. ii, p. 46 and 47. Note on p. 47, vol. ii, Bichat's Anat. Gen. instead of parallel, and it will be seen that a greater, degree of force is necessary to cut them. The fibres of the external layer do not reach the internal coat, but take their insertion upon those of the deeper seated layers. These fibres are bound together by a very small quantity of cellular tissue. This coat is elastic and friable. It breaks or its fibres separate under the action of the ligature. Vessels cannot be traced into it, though they doubtless exist, and indeed, Manec affirms that he has seen them in very young animals.* The third or internal coat is still less vascular, and is equally, or indeed, more friable than the last. Some persons have considered it as mucous, some as serous, and Velpeaut compares it to cuticle, serous membrane or cartilage, in view of the low degree of vitality it possesses, and the difficulty with which it takes on inflammation, unless this be transmitted to it from neighboring organs suffering under disease. He says it contains no perceptible fibres or vascular canals: that it is in fact only a homogeneous, lamellar substance: a kind of varnish in some respects similar to the transparent eornea, or to the substance of the nails or horny tissue in general Bichat says when treated by maceration it takes on a rosy tint, resembling the cartilage of the fœtus and the fibro-cartilage of the adult, when these are submitted to the same experiment. But this it does less regularly than the tissues named or than the arterial coat last described.‡ Manec says it is, on its inside, smooth, polished and shining, like serous membrane, from which it differs, however, by a peculiar character easily seen, a velvety appearance, which serous membranes have not. Its transparency, he says, is like that of ground glass, while that of serous membrane is like dirty polished glass. It is endowed with a lower degree of organization than serous membrane, according to Manec, being made up of globular molecules massed together, whereas in serous membranes these molecules are arranged in fibres. It is exceedingly brittle, and yields without offering much resistance to the action of the ligature. Its inner surface is bedewed with a smooth, unctuous fluid, calculated to facilitate the flow of the blood along the artery. It is upon parts constituted in the manner thus briefly described, that ligatures are applied: are these arrangements such as will adapt them for bearing well the action of the constricting thread or the reverse? Bichat thought the latter. He says, "It is beyond a doubt that there is no other tissue so fragile, if I may use the word, as the arterial; none, consequently, less proper for being embraced by ligature. Why is it that this should be the only * Traite Theorique et Pratique sur la Ligature, &c. Manec. Paris. 1832. + Mott's Velpeau, vol. ii., p. 2. + Op. Cit., p. 44. Op. Cit., p. 6. one on which it is necessary to apply them?"* This question can only be answered by glancing at the phenomena which result from tying an artery. The first step in such an operation is laying the artery bare, which must be done by an incision through the soft parts, under which the vessel lies, sufficiently free to admit of easy manipulation. If the ligature is to be applied to the end of an artery already cut, as in a stump or other wound, it should not be drawn out further than is necessary to admit of the application of the thread. These precautions will enable the surgeon to place the ligature around the artery without disturbing it much in its sheath; a precaution upon which the success of the operation will mainly depend for if the connections of the vessel with the sheath are broken, the nutrient arteries or vasa vasorum will of necessity be destroyed (for it was seen above that these reach the vessel from this direction) and the vital energy of the vessel be impaired in proportion to the extent of injury. But the sheath itself should be laid open only to the extent necessary for reaching the artery. The ligature being passed round the artery and the knot made, this is drawn, by means of the finger ends, till the sides of the artery are pressed together, when the flow of blood of course is interrupted. The traction upon the ends of the thread being continued, the two inner coats give way, leaving a clean smooth cut, (if a small thread has been used, but a bruised and lacerated one if the ligature is large) and the outer coat is puckered in, so that its sides are brought into perfect contact. The divided edges of the two coats which have been cut are pressed in by the action of the thread upon the outer coat, so that they are placed in contact and the two parts of the artery immediately above and below the ligature, are brought into a conical shape. Two processes, very different in themselves, but both depend. ing upon the action of the ligature upon the artery, and both highly important towards the end in view, are immediately put into action. From the cut surfaces of the two inner coats of the artery exudes that same plastic lymph which we see furnished from other wounded surfaces, and it here performs the same service as elsewhere. It serves to form a re-union between the divided edges of the cut surfaces: at first very imperfect, fecble and easy to be separated; but gradually acquiring more consistency and strength, at length offering a perfect and solid barrier against the passage of the blood beyond this point. So that after a time this fluid would be arrested in its course here even if the ligature were removed: which in fact it is, (as will be seen) by the sloughing away of that part immediately pressed upon by the thread. At the same time that this * Op, Cit., Vol. ii., p. 49, |