and the lining membrane of the latter organ extensively ulcerated.

In the Thorax. Evidences of pulmonary, pleuritic, and pericardial inflammation have been found. Congestion, apoplexy, hepatisation and suppuration of the lungs. Tubercular deposits and cavities. Effusion of lymph and serum into the pericardial and pleural cavities, and adhesions between the parietal and pulmonary portions of the pleura. The ventricles of the heart have been found studded with fibrinous deposit. The left mammary gland inflamed, and several of the axillary glands inflamed and purulent.

Head. The surface as well as sections of the brain have been found studded with hæmorrhagic spots, and the left eye diseased, disorganised, and purulent.

And now, gentlemen, having laid before you as complete a summary of the clinical history of the disease as my time will allow, I would ask you, in conclusion, to consider how far, looking to the multifarious details which constitute that history, you are prepared to assent to the doctrine that the primary seat and source of the disease is in the crural veins, and that crural phlebitis is its proximate cause. In connection with the affected extremity, we have seen this lesion of the veins associated with kindred lesions of almost every other important organ and structure; and in connection with the constitution at large, with grave disease of almost every vital organ. How, then, is it possible, in view of these facts, to assign to the lesion of the veins that prominence and priority which is implied in this theory? In that period of the history of medicine when disease and morbid actions began to be studied by the light and guidance of morbid anatomy, there was scarcely

a fever or a malady which was not traced to, and assumed to depend upon, some particular local lesion; a doctrine which time and opportunity have sufficiently refuted. But the theory of phlebitis as the proximate cause of phlegmasia dolens, was propounded with the very earliest glimmering of light which dawned upon it from that source, even with the first dissections; and if our views of morbid action were bounded solely by the evidences of anatomy, such theory would still be the most plausible, as it is probably the most apparent. But in more recent times we have learnt the necessity of calling in to our aid other sources of information for the right interpretation of disease. We have been taught to look to its natural history, its origin, progress, and terminations, and the effect of remedies, as giving equal light, and affording equal information; and, tested by these, the conviction is irresistible, that the phlebitic theory rests upon too narrow and contracted a basis, and that, looking to the extensive series of morbid actions, and the widely-spread evidences of disease throughout the body which mark its progress, we are led to the conclusion that we can only adequately account for it and for them by assuming that they are the common effects of some more general and diffused morbific cause; and thus, from the study of clinical facts alone, we are, I would submit, compelled to ignore the phlebitic theory of the disease in favour of some other, the nature of which I will further endeavour to elucidate by another series of investigations in the ensuing lecture.

LECTURE II.

PHYSIOLOGICAL RESEARCHES INTO THE ORIGIN OF PHLEBITIS AS CONNECTED WITH THE PATHOLOGY OF PHLEGMASIA

DOLENS.

Delivered November 25th, 1861.

MR. PRESIDENT AND GENTLEMEN,-In the preceding lecture I endeavoured to lay before you a comprehensive analysis or epitome of the clinical history of phlegmasia dolens, with especial reference to the question of the probable nature of its proximate cause. And having submitted to you the grounds upon which I venture to maintain the insufficiency of phlebitis, as of any other local lesion, to account satisfactorily for the phenomena of so complex a disease, judged of by clinical evidence, I shall proceed to place before you in the present the conclusions I have arrived at upon this point from physiological research-from researches which were specially undertaken for the purpose of determining how far crural phlebitis, in a pure and uncomplicated form, was capable of giving rise to a malady so complex, or how far phlebitis, generically, might not be traced up to a higher and more general morbific agency, the operation of which simultaneously upon the veins and the different other organs and structures of the affected limb would adequately account for all the very varied lesions which are met with in the disease.

Let me, however, premise briefly what I conceive to be the

questions more especially to be solved by physiological research.

Reverting, then, to the various theories of the disease which have been proposed, we have seen that the one only which has stood the test of anatomical investigation is that which ascribes it to crural phlebitis-phlebitis, with a few exceptions, having been invariably found upon post mortem examination, and constituting, indeed, the most important anatomical lesion discoverable in the affected extremity. Discarding, then, the lesions of the nerves, lymphatics, and other anatomical constituents of the limb, occasionally met with in post mortem examinations, as being incidental rather than essential,-and although very generally, yet not invariably, met with on dissection,-it follows that our inquiry becomes limited, as already stated, to a determination of the question of how far crural phlebitis, in a pure and uncomplicated form, can give rise to the very complex phenomena of the disease, or how far phlebitis itself can be traced up to, and deduced from, some more general and diffused morbific agency capable of producing the various other local and general symptoms which are coordinately met with.

Now, in the investigation of this subject, it will be necessary to bear in mind that the symptoms of phlegmasia dolens are not merely such as are dependent upon an obstructed condition of the principal veins of the extremity, but comprise others which are characteristic of other lesions. Thus, the character of the swelling is not simply that of oedema, but it is tense, hot, and elastic. The condition of the nerves is one of exalted sensibility, often amounting to the most agonising pain. The motor powers of the limb are impaired to a degree which, in some instances, verges upon positive paralysis, and in addition to the tension and obstruction of the chief veins, there is often

redness and tenderness in the course of the lymphatics and principal cutaneous nerves. Now, the first question it was proposed to investigate was, how far these manifold forms of local lesion would follow upon crural phlebitis artificially produced.

I. EFFECTS OF CRURAL PHLEBITIS IN PRODUCING THE SYMPTOMS OF PHLEGMASIA DOLENS.

To determine this question I had recourse to the three following series of experiments; first, to ligaturing the iliac veins, and observing the resulting phenomena at different periods after the operation; secondly, to extensive irritation of the lining membrane of the same vessels by means of chemical and mechanical irritants; and thirdly, to sustained compression of the femoral veins by means of firm metallic compresses. For the particular details of these experiments, I must refer you to my paper published in the thirtysixth volume of the Medico-Chirurgical Transactions,—the time allotted for the delivery of these lectures, allowing me to give only a very general summary of what was observed, and which may be thus epitomised.

Effects of Ligaturing the Iliac Veins. The constitutional effects which follow upon ligature of the iliac veins would appear to be of a very transient character, and to be referable to the extensive wound which is necessary to expose the vein rather than to the actual operation itself. They were most marked and severe on the day of the operation, during which the animal remained quiet, subdued, and disinclined to take food; at the end of twenty-four hours they had in a measure subsided, and from this time almost rapidly disappeared. The local effects were also of a transient rather than of a persistent character, and were confined, in a great measure, to swelling,