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THE

BRITISH AND FOREIGN

MEDICO-CHIRURGICAL REVIEW.

JULY, 1859.

PART FIRST.

Analytical and Critical Reviews.

REVIEW I.

Course of Lectures on the Physiology and Pathology of the Central Nervous System, delivered before the Royal College of Surgeons of England, in May, 1858, by E. BROWN-SÉQUARD, M.D. Illustrated by numerous Engravings, representing the principal Experiments and Pathological Cases. (From the Lancet,' 1858-59).

In a Lecture delivered by Schiller at Jena in 1789, on the study of Universal History, the poet draws a striking contrast between the empiric or "trader in science," and the "real philosopher" or lover of wisdom; and in no respect is that contrast more remarkable or more true, than as to the reception which each gives to new discoveries. Of the former he remarks, "Every extension of the boundaries of the science by which he earns his bread is regarded by him with anxiety, since it occasions him fresh labour, or renders his former labours useless: every important innovation or discovery alarms him, for it breaks down those old school formula which he had taken so much pains to acquire: it endangers the entire produce of the toil and trouble of his whole previous life." On the other hand, “new discoveries in the field of his activity, which depress the trader in science, enrapture the philosopher. Perhaps they fill a chasm which the growth of his ideas had rendered more wide and unseemly, or they place the last stone, the only one wanting to the completion of the structure of his ideas. But even should they shiver it into ruins, -should a new series of ideas, a new aspect of Nature, a newlydiscovered law in the physical world, overthrow the whole fabric of his knowledge, he has always loved Truth better than his system, and gladly will he exchange an old and defective form for a new and fairer one."

We have thought it not inappropriate to call the attention of our 47-XXIV.

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readers to the noble sentiment we have italicized, by way of preface to the enquiry through which we purpose to conduct them, as to the merits of the most important among the numerous sets of researches carried on by one of the most distinguished experimental physiologists of our time, -namely, those investigations into the Physiology and Pathology of the Nervous System, of which M. Brown-Séquard gave an account (with experimental illustrations) in a course of lectures delivered by him last summer at St. Bartholomew's Hospital, and afterwards repeated at the Royal College of Surgeons, by the special request of its Council. The slight notice which we have already given of the results of some of these investigations (vol. xvii., p. 407 et seq.) by no means relieves us from the responsibility of now critically examining into the value of the entire series; and we are sure that no one is more desirous than M. Brown-Séquard himself, that their merits should be tested by a careful scrutiny into the validity of his methods, the accuracy of his statements, and the justice of his deductions. If they prove able to bear such an ordeal, they are fairly entitled to take rank as physiological verities, notwithstanding their contrariety to much that has been previously received as true. We are not among those who are disposed to stand by a doctrine, merely because it is currently accepted, or because it has been taught by men whose authority we hold in the highest respect. Such reasons for upholding it are good against the slight assaults of such opponents as are themselves deserving of but little credit; but when a formal contradiction is given even to our most cherished beliefs, by men whose patient search for truth, and whose capacity for its discovery, command our highest respect, we do not see that any other honest course is left to us, than that of candidly weighing the new facts and arguments against the old, assigning to each its worth according to the best judgment we can form, and striking the balance without more regard to our previous conviction than is found to be justified by the stability of the base on which it rests.

Now, in endeavouring to form this kind of estimate of the merits of M. Brown-Séquard's doctrines, as compared with those which have been currently accepted in Physiology, we must confess in limine that we are not able to speak from personal experience as to more than a small part of his experimental results. But we feel scarcely less readiness to credit those which we have not ourselves witnessed, than to trust our own observation as to those which we have; so great is our confidence in M. Brown-Séquard's aptitude for observation, which allows no phenomenon to escape him, in the exactness with which he not merely performs his operations but subsequently determines the precise nature of the lesion he has inflicted, and in the scrupulous truthfulness with which he records every fact which bears upon the question at issue, whether or not it is favourable to his own view of the case. This confidence is founded in part on the careful watch we have ourselves kept on M. Brown-Séquard's scientific course, from the time when his researches first began to attract attention about twelve years ago, and on the estimate we have formed of his character from

the personal acquaintance which it was our good fortune to commence with him not long afterwards; and in part on the fact that several of his capital experiments have been performed before a Commission of the Société de Biologie, consisting of MM. Cl. Bernard, Bouley, P. Broca, Giraldès, Goubaux, and Vulpian, whose report drawn up by M. Paul Broca, bears the fullest testimony to the accuracy with which he has described both the operations and their results.

The Course of Lectures which M. Brown-Séquard has published in the columns of the Lancet,' is much fuller in detail than that which he actually delivered at the College, especially in regard to the evidence supplied by Pathological observation; still on many points it is far from being complete; and we think that we shall do most justice both to him and to our readers, by limiting our discussion of his doctrines to the following questions, which we shall take up in succession :—

1. The relative functions of the Anterior and Posterior Roots of the Spinal Nerves.

2. The channel through which Sensory Impressions are conveyed from the Spinal Nerves to the Encephalon.

3. The Decussation of the Conductors of Sensory Impressions in the Spinal Cord itself.

4. The channel through which Motor power is conveyed from the Encephalon to the Spinal Nerves.

5. The motor action of the Sympathetic system on the walls of the blood vessels.

6. The action of the Nervous System (especially, though not exclusively, its Sympathetic division) upon the Organic functions of Nutrition and Secretion.

I. The first question to which we have to apply ourselves,-that of the Relative Functions of the Anterior and Posterior Roots of the Spinal Nerves, is one which, although commonly supposed to have been conclusively settled by Sir C. Bell and his immediate followers, still presents certain points of difficulty. And it is obvious that until these shall have been elucidated, no conclusions regarding the functions of the different columns of the Spinal Cord can be satisfactorily drawn either from experiment or from pathological observation. It was early observed by Magendie, that although pain is obviously the principal result of irritation of the posterior roots, and muscular contraction the principal result of irritation of the anterior roots, yet that local movements are induced by irritation of the posterior roots, and that pain is obviously excited by irritation of the anterior; and hence he was for a time erroneously led to the conclusion that each set of roots is subservient to both functions, the posterior being chiefly but not exclusively sensory, and the anterior chiefly but not exclusively motor. Further enquiry, however, has served to demonstrate the erroneous nature of this conclusion; the movements excited by irritation of the posterior roots, and the pain induced by irritation of the anterior, being clearly due in each case to the participation of the nerve-roots not thus experimented on. For if, before irritating the posterior

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