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mine, as each claimed the whole, and the dispute gave rise to a bitter feud between them.
12. He discovered the lymphatics in birds.
13. Amongst the most important improvements in practical surgery of the age in which Hunter lived, and which may be classed among his discoveries, was the operation, first suggested and practised by himself, of tying the femoral artery for the cure of popliteal aneurism. Considered simply in the light of an operation for the cure of aneurism, in which a ligature was thrown round the artery above the aneurismal tumour, leaving the tumour itself unopened, Hunter's operation was certainly not new, because Anel had performed at Rome, in 1710, precisely such an operation on the brachial artery, for the cure of an aneurism at the flexure of the elbow, and with complete success; but considered in the light of an operation based on the principles that the collateral blood vessels would enlarge and carry on the circulation when the main trunk was rendered impervious, and that the aneurismal tumour would be gradually removed by the action of the absorbents, Hunter's operation was entirely new. also in respect to its application to popliteal aneurism. priority which has been set up for Desault is absurd, for in his operation the artery was tied in the ham-not in the thigh; and though he did not open the tumour, it burst of itself, so that the operation affords no parallel with that of Hunter, and as regards results, was altogether inconclusive.
It was new
Several other of Hunter's particular discoveries have been already mentioned in connexion with his general doctrines and views, and more might be cited, but the foregoing may answer the purpose of the present brief survey.
We have thus endeavoured to give a sketch of what Hunter did for science, derived chiefly from an examination of his writings. But he has left a record of his thoughts and his discoveries far more interesting and impressive than any writing, in that museum, which is viewed by all capable of appreciating it with daily-increasing wonder. This is in reality by far the most remarkable of Hunter's works, and is, to our apprehension, utterly different in its whole scope and meaning from everything else that it ever entered into the mind of man to conceive or into his plans to execute. Anatomical museums, previously to that of Hunter, had been merely the repositories of certain objects calculated to convey information as to particular facts, or to exhibit points of individual interest or curiosity. Each object spoke for itself, and it spoke of nothing further. A museum which should carry out an abstract physiological principle through an almost endless series of forms, each exhibiting some new adaptation of structure to its manifestation, was a thing which had never been even dreamed of. Yet such was Hunter's museum. In the physiological portion of it at least, there is scarcely a preparation which stands alone. Each stands in relation to that which precedes and that which follows it, and each forms a link in an unbroken chain of investigation into the develop
ments of the vital force. The whole is one continuous train of what may be called visible and tangible reasoning. It addresses us in an extraordinary symbolical language, in which the powerful but peculiarly constituted mind of Hunter delighted to embody its conceptions. As we have already hinted, he had in his composition some of the elements of a poet, and we may now add of an exceedingly great poet. That he was a man of vast imagination cannot be doubted, otherwise he never could have formed so stupendous a design as that of thus turning to shape the universe of life and giving it a local habitation. The German Fichte has maintained that the whole universe is the development of a “divine idea," which it is the province of poets and philosophers to interpret to man; to which view the practical objection is, that none but a mind commensurate with that of the deity could take in the idea, or be equal to the task of expounding it; but assuredly, as far as life was concerned, Hunter appears to have been possessed, more than any other mortal, with some such divine idea, and being gifted with scarcely an ordinary command of language, he was at once driven by a natural deficiency and guided by the singularity both of his genius and of his subject, to the adoption of a mode of expression of all others the most suitable, and compared with which all verbal description or illustration would have been poor and unemphatic. His tongue was not fluent of speech, and his pen was not that of a ready writer, but his hand, long skilled in dissection, became the readiest and the most faithful interpreter of his thoughts.
ART. I.—Sur une Fonction peu Connue du Pancréas, la Digestion Des Aliments Azotés. Par LUCIEN CORVISART.-Paris, 1857-58. Pp. 123.
On an Almost Unknown Function of the Pancreas, the Digestion of Nitrogenous Food. By LUCIEN CORVISART.
We may say at the outset that this is a truly workmanlike effort in the cause of science, and that whatever success it may achieve will be well deserved. With this brief preamble let us on.
The author proposes to examine what are the transformations which the principal azotized foods undergo from the gastric and from the intestinal digestion; what are the stages of these transformations; what is the quantity of each food which each of these digestive processes changes; and how much a fixed quantity of gastric or pancreatic juice is capable of digesting. The result of numerous careful experiments is summed up in the following propositions, which we abstract: (1) The pancreas digests azotized food in a precisely similar way to the stomach; it does not act upon matters already digested by the stomach, but upon those which are little or not at all altered. (2) The digestive action of the pancreas may equal that of the stomach, for though the amount of its secretion is ten times less than that of the stomach, it is ten times richer in ferment (pancreatine). (3) The pancreatic fluid acts equally well in digestion, whether it be alkaline, neutral, or acid, and thrice as rapidly as the gastric. (4) The disintegration of the food which takes place in the stomach enables the pancreatic juice to act more rapidly than it would otherwise. (5) If pepsine and pancreatine are mixed together they no longer exert the same action that they would when separate-in fact, all digestive power may be lost from their destroying each other. This mixing is prevented in the body by the pylorus, by the absorption of the pepsine in gastric digestion, and by the bile, which nullifies the activity of the gastric ferment. (6) Bile is precipitated by the acid of the chyme, and does not itself precipitate the gastric pepton. (7) The kind of food has a material influence on the quantity of pepton which the two digestions, the gastric and pancreatic, can produce. Thus musculine and caseine furnish thirty grammes of pepton, while an equal quantity of gelatigenous tissue, or albumen, furnishes only fifteen grammes. (8) Both digestions destroy the most characteristic properties of the several foods. (9) The generic characters of the peptons are solubility
in water, whether acid, neutral, or alkaline; incoagulability by heat; non-precipitation by acet. plumb. for the most of them. The peptons resulting from either digestion, as a rule, do not contain albumen, at least not more than exists in the normal and pure pancreatic fluid. (10) During the first three hours after food there is no material absorption into the radicles of the portal vein, but yet there occurs a considerable increase in the proportion of albumen contained in the blood. This increase the author ascribes to the agency of the pancreatic juice poured into the duodenum at a time when it is destitute of ingesta; he believes that in the vena porta the globules and the fibrine of the blood are transformed by the absorbed pancreatic secretion into caseiform albumen. (11) No really differential character has been made out between the azotized matters called extractives, and the albuminose produced by gastric or pancreatic digestion. Now, the chyliferous vessels, the vena porta, and its continuation, the hepatic veins-i.e., the vessels which receive most directly the products of digestion, are much richer in extractive matters (albuminose) than the rest of the blood; and so it may be remarked they are in glycose.
Certain pathological inductions may be made from the above conclusions. (A) A duodenal dyspepsia may be induced by the absence, vitiation, or insufficiency of the pancreatic juice. The uneasiness attending this is felt from two to three hours after taking food, and is deeper seated than in gastric dyspepsia. (B) Duodenal dyspepsia may also be induced by any condition which permits unabsorbed or unneutralized gastric juice to mingle with the pancreatic. An excessive amount of gastric secretion, or an open state of the pylorus, or an insufficiency in the biliary secretion, may all have this effect. (C) The derangement of the intra-venous (portal hepatic) digestion may also occasion a form of dyspepsia.
We have not herewith presented our readers with even a complete summary of our author's views, but we cordially advise them to study the work for themselves. It has the great merit, so commonly possessed by French writers, of being clearly and precisely written; and it has the further recommendation (which the satiated mental appetite will appreciate in these days of book-surfeit) of being short, containing altogether but one hundred and twenty-three pages. We would it had been possible for us to have obeyed the author's injunction, and to have repeated his experiments. Only so could we have really qualified ourselves to criticise accurately his work. But in default of doing this ourselves, we trust that what we have said will induce some of our readers to undertake the duty, and so "sa conviction . . . . dans tous les cas servira la science, si peu avancée sur ce sujet."
ART II-On Poisons in Relation to Medical Jurisprudence and Medicine. By ALFRED S. TAYLOR, M.D., F.R.S., Professor of Medical Jurisprudence and Chemistry in Guy's Hospital, &c. Second Edition.-London, 1859. pp. 863.
TOXICOLOGY, whether we consider it in relation to the science of life, to the detection of crime, or to the chemical art of discovering dele
terious substances in organic mixtures, has made immense progress during the eleven years which have elapsed since the appearance of the last edition of this work. The study of the action of poisons on the living organism, which constitutes what may be strictly called the science of toxicology, has been advanced by several extended researches undertaken with a purely scientific object, and without any view to the juridical relations of the questions investigated. In the practical part of the subject a similar progress has been made, and has no doubt been promoted by the occurrence during the last few years of several important criminal trials, which have tended to expose many fallacies, and to establish some valuable principles in medical evidence, and generally to stimulate investigation by drawing public attention to the practical bearing of questions which had before a merely scientific interest.
We are therefore not at all surprised at being told by Dr. Taylor, in his preface, that he has found it impossible within the same limits to treat of all the subjects comprehended in the former edition; and that he has found it necessary to confine himself even more strictly than before to the practical objects of the work. If any one, misled by the title, should take up Dr. Taylor's book, hoping to find in it an exposition of the relations of toxicology to the science of disease, he would be disappointed. In the comparison of the phenomena of disease with those of poisons we have a most valuable means of pathological investigation. On the one hand, we have a poisonous agent capable of being readily isolated, weighed, measured, and experimented on; on the other, the agent is subtle, and for the most part, we know neither whence it comes nor whither it goes; and even when we have some knowledge of its origin, we cannot seize upon it, or define its nature in any other way than by describing its effects. It is the study of the modus operandi of poisons, as affording the means of making the comparison we have indicated, which constitutes toxicology con-sidered as a branch of the science of medicine; but in this sense, as we have already hinted, it is not included in Dr. Taylor's plan. His book is to be regarded merely as a repertory of all those facts and principles relating to poisons which bear on the detection and proof of crime, its object being to aid the lawyer in the due appreciation of medical testimony, and to fit the medical practitioner for his duties as witness. As a treatise on poisons in relation to crime we think that the work in its present form is the best and most comprehensive in existence in this or in any other language, and that all the modifications which have been introduced into the present edition will be found to be improvements.
As regards the employment of medical men as scientific witnesses, we adhere to the opinion that we expressed ten years ago in our former notice, that it would conduce to the interests of justice, no less than to the credit of the medical profession, that in every case of supposed criminal poisoning the aid of a professed toxicologist should be obtained, and that he should conduct the analysis and be answerable for the whole chemical evidence. We venture to say that a medical