the fibres having become thickened, and the neuroglia, the element now under consideration, being much atrophied. One result of this atrophy of the packing material is to render the brain substance rapidly brittle and stringy when subjected to chromic acid, and to cause sections to split in the direction of the fibre under very slight pressure, like over-dried wood. In spinal cords where atrophy exists these splits are well seen, resembling the divergent cracks of the stump of a tree after exposure to the air and sun. The fibres in such sections are very considerably thickened, as if endeavouring to supply the place of the lost neuroglia. Nuclei are rarely seen, and when present are larger than normal and irregular in shape. Where this condition exists colouring material is very readily absorbed by sections, and so generally as to but slightly differentiate between white and grey matter. Atrophy of neuroglia is only recognisable where the general brain wasting has been extreme.

Colloid degeneration.-Colloid degeneration is one of the most important and interesting forms of brain lesion, being, I believe, the primary pathological change in certain of the most prominent and well-defined varieties of insanity. As its relations to symptoms must be considered at length in the concluding portion of this paper, I will merely say now that good reason exists for believing that on colloid degeneration depend those cases in which the vague term "brain disease" is employed to indicate that a primary affection of that organ is the exciting cause of the mental symptoms.

In its earliest stages this abnormal condition shows itself in circumscribed semi-translucent spots scattered irregularly over the surface of the section, varying in size from the 1-4000th to the 1-2000th of an inch in diameter; they have well-defined irregular edges, and their contents are molecular in appearance. In fresh specimens, however, this molecular appearance is not observable, and colloid bodies appear as round or oval in form, having a distinct wall containing a clear homogeneous, transparent, colourless plasm, and occasionally showing a small nucleus, but no nucleolus. Colloid bodies are not colourable by carmine, however strong the solution and however long they are submitted to it. They appear first in the white matter immediately contiguous to the cortical substance, but as the disease advances they become diffused outwards and inwards. In extreme cases the appearance of sections containing them may best be compared to a slice of sago pudding, for they exist in such large numbers as almost completely to fill the field of the microscope, separated slightly from each other by a fine granular material. Although readily recognisable when set up in Canada balsam or turpentine, the characteristics of colloid degeneration are best brought out by glycerine.

I feel strongly inclined to regard this as a form of degeneration of

the nuclei of the neuroglia; it is first seen and is best marked in the white matter, but in certain specimens in which it occurs in the grey matter cells have been seen which are undergoing, or have undergone, changes in many respects resembling those noticed in the nuclei of neuroglia. It is not associated with proliferation of nuclei. Careful study of a large number of specimens leads to the conclusion that the nuclei are the original seats of the disease, for in all cases in which colloid degeneration shows itself they are to be seen more or less departing from normality; in fact, it may be safely stated that they are always unhealthy, and appear to merge gradually into the colloid condition.

There are points of resemblance (on paper) between colloid degeneration and miliary sclerosis, but there are many differences manifest to the observer which entitle them to be regarded as distinct pathological conditions; of these the chief are that colloid bodies do not undergo the same gradations of development as miliary sclerosis, that they do not push aside the fibres, and that they never can be removed as a separate substance from dried sections in which they exist. It is subject for regret that the several appearances cannot be figured in this place.

Dr. McKendrick, Assistant to the Professor of Physiology in the University of Edinburgh, when conducting experiments on the functions of the corpora striata, found in sections of pigeons' brains which had been traumatically injured certain bodies in the neighbourhood of the healing cerebral substance. These were recognised as colloid bodies. Dr. McKendrick kindly communicated this fact to me, and with his permission I followed up the observation to some extent. The brains of birds were injured by being stirred up or incised with tenotomy knives, and time allowed for the process of healing. At various periods after the infliction of the injury the birds were killed and sections of the wounded cerebra prepared by the chromic acid process. In every case in which the injury was of ten days' standing colloid bodies were found, and they increased in number up to the seventeenth day; they were seen in the neighbourhood of the cicatrix in clusters, their size being much smaller than in the human subject, never exceeding the 1-6000th of an inch in diameter, but otherwise they presented identical characteristics. Further remarks on this line of experimentation are reserved until the series of observations is more thoroughly worked out.

103-LII.

14

III.-Original Notes of Dr. W. Hunter's Lectures on Anatomy, Physiology and Surgery.

Introduction.-I bought some months since, at a sale in London, the copy from which the following extracts are taken. It is in four quarto volumes, paged consecutively from 1 to 1161; towards the end (pp. 1163-1335) are J. Hunter's lectures. It is fairly written; unfortunately, pp. 1007-1012 are wanting. The titlepage of the first volume is dated January 18, 1781, and on the first page is the signature, Thomas Denison. The first fifteen lectures contain the introduction, the general anatomy and physiology of the blood, the vascular system, the absorbing system, the glandular system, &c.; pathological and other subjects are occasionally discussed, e.g. the diseases of the arteries, phlebotomy. Special anatomy follows, and is treated in a similar way. The operations of surgery begin at p. 971, and the course concludes with the art of embalming.

Notes of lectures, taken by a student, must always fail to give any correct idea of the lectures themselves; yet imperfect as the present manuscripts evidently are, they furnish at least an outline of the subjects treated, and we find in them, scattered here and there, little portions interesting in themselves, but far more as coming from one so celebrated in his day as William Hunter.

The author of an excellent sketch of W. Hunter1 states that "in the library of the Royal Medico-Chirurgical Society there are several volumes of manuscript lectures of Hunter. These are of great interest, as indicating the method of his teaching. On reading portions of the manuscript we find, however, that they are not notes by the lecturer, but by students who were attending the courses. One volume, written by a careful hand throughout, bears on the cover the following:- Anatomical, Physiological, and Chirurgical Lectures, by Dr.. Hunter, 1759.' Three other small books in manuscript are entitled, A Course of Anatomical Lectures by Doctor Hunter, January 20th, 1773.' A third volume of manuscript, very carefully written out, gives, again, the 'Anatomical Lectures,' without date, but with writer's name, John Ashley; and a fourth volume in manuscript, including the lectures on the 'Gravid Uterus,' is by Dr. Skeete. The care with which these manuscripts have been copied indicates the value attached to them by the writers. In the library of the Medico-Chirurgical Society there will also be found, bound up with the last two introductory lectures of Hunter, some papers relating to his intended plan for

''Med. Times and Gazette,' 1859, i, 502.

establishing a museum in London for the improvement of Anatomy, Surgery, and Physic."

This writer describes Hunter1 as "a gentleman and a scholar. He can talk about everything, and knows all that is going on. The antiquary brings him an ancient coin, and finds a colleague who can discuss the points of date and of value. The naturalist shows a fossil bone, and straightway the two are at home and comfortable. The historian discourses with him as a brother; and with the classic he crosses excellent Latin. With the ladies his conversation is charming, for his voice is musical, his expression faultless, and his manner gallant." Hunter began to lecture in the winter of 1746, succeeding Sharpe in his course on the operations of surgery. "He is said to have experienced much solicitude when he began to speak in public, but the applause he met with soon inspired him with courage; and by degrees he became so fond of teaching, that for many years before his death he was never happier than when employed in delivering a lecture." He continued to lecture till 1783; "at length, on Saturday the 15th of March 1783, after having for several days experienced a return of wandering gout, he complained of great headache and nausea. In this state he went to bed, and for several days felt more pain than usual both in his stomach and limbs. On the Thursday following he found himself so much recovered that he determined to give the introductory lecture to the operations of surgery. It was to no purpose that his friends urged to him the impropriety of such an atttempt. He was determined to make the experiment, and accordingly delivered the lecture, but towards the conclusion his strength was so exhausted that he fainted away, and was obliged to be carried to bed by two servants." 3 He died on the 30th of the same month.

2

"As a teacher of anatomy he has been long and deservedly celebrated. He was a good orator, and having a clear and accurate conception of what he taught, he knew how to place in distinct and intelligible points of view the most abstruse subjects of anatomy and physiology. Among other methods of explaining and illustrating his doctrines, he used frequently to introduce some apposite story or case that had occurred to him in his practice, and few men had acquired a more interesting fund of anecdotes of this kind, or related them in a more agreeable manner. He had the talent of infusing much of his ardour into his pupils, and if anatomical knowledge is more diffused in this country than formerly, we are indebted for this, in a great measure, to his exertions."-THOMAS WINDSOR.

1 Loc. cit., p. 391.

6

S. F. Simmons, An Account of the Life and Writings of the late William Hunter.' London, 1783, p. 11.

3 Simmons, loc. cit., p. 63.

Ibid., loc. cit., p. 68.

Circulation of the Blood (p. 70).-Some have said that the action of the arteries contributes nothing to the circulation of the blood; but I am of opinion that they contribute to it greatly and independently of their elasticity; which power, I think, may be called muscular. For, endeavouring to inject milk into the mesenteric veins by the mesenteric arteries in a dead subject, I met with great difficulty, but in a living animal it readily passed from the artery to the vein without any further force than filling the artery with a syringe, and then stopping the orifice with the finger it passed of itself.1

Rapid pulse in the healthy (p. 74).-We sometimes find a pulse always beating in health 100 or more; Dr. Askew, in common health, had it beat 150 in a minute for many years.

Parts tinged with bile (p. 101).-By the parts surrounding the gall-bladder being tinged, it would appear that the bile itself would transude; but Mr. J. Hunter says that this does not take place till after death. He is convinced of this from having opened several live animals and others just dead, in order to examine those parts.

The lymphatics absorb (p. 111).—I received the first hint of the lymphatics being absorbent vessels from a friend's asking my opinion of Dr. Freke's chirurgical publication about the year 1748; to which I answered that I had not read it. My friend then mentioned Mr. Freke's advising a surgeon in venereal cases to cut out a bubo from the groin, for he said he would by that means eradicate the poison, which, he supposed, was conveyed in some way or other from the genitals to the inguinal gland and detained there. This struck me immediately, so that it came into my imagination that the lymphatic vessels were the conveyors of the poison. Taking up the subject upon this supposition, I was by numerous experiments and observations soon convinced that he was right in his conjecture.

Cause of difficulty in reducing dislocations (p. 257).—It was the general doctrine that, when a bone was luxated, the capsular ligament stretched and dilated before the head of the bone. But upon examining this ligament in a dead subject, one would conclude à priori that it is too strong and tight to admit of luxation from external force, without being ruptured. Dr. Hunter says that he believes that the capsular ligament is always torn, for he has several times attempted to luxate the humerus and femur in a dead subject, but never could effect it without tearing through the capsular ligament. These trials, he thinks, are conclusive, because mechanical force acts exactly the same on the dead as on the living subject. He says the phenomena of luxations prove this theory. Sometimes a dislocated bone is reduced with great ease, at other times not with

1 I have corrected here and in the following extracts the punctuation and some verbal errors.-T. W.