Hence the phthisis of scrofulous persons is in most cases really dependent on tuberculosis, but there is no denying that it may also begin and end as cheesy pneumonia. Indeed, it is quite common for such persons to have a predisposition to catarrh and to inflammations of the respiratory organs. The inflammatory products in the lungs may, in certain circumstances, become caseous, and so set up phthisis either alone or combined with tuberculosis. Besides, my experiments proved that purulent inflammation in different organs can be excited by inoculation, in addition to true tubercles; and therefore it is possible that cheesy pneumonical deposits, as well as tuberculosis, may be developed as the direct result of the resorption of scrofulous matter.

Again, the last-mentioned experimental facts compel us to consider whether the simple inflammatory affections of scrofulous subjects are, or are not, in certain conditions, secondary and due to the resorption of cheesy matter in lymph-glands. I refer to obstinate cutaneous eruptions, inflammation of bones and of joints, troublesome eye affections, &c. Such cases are, no doubt, generally primary, and swollen glands secondary; but there are also many instances in which the glands become tumefied and caseous after an inconsiderable inflammation of the skin or of the mucous membrane, which soon recedes; then at a much later period serious mischief makes its appearance in various organs. Here we are at liberty to refer the latter morbid process to the same long-standing cachexia from which the former and less severe affections originated, an explanation hitherto regarded as the only correct one; or we may consider it as caused, in part at least, by resorption. Let us not come to a too hasty decision on this important question, but rather let us try to solve the problem by the aid of numerous and searching experiments.

I have already in a former division of my work discoursed upon the nature and constitutional causes of scrofulosis. The tendency of the glands to caseation may be traceable to an inherited abnormality in the structure of the lymphatic system. But undoubtedly scrofulosis can also be acquired. Bad air and insufficient or unsuitable

food stand foremost amongst the conditions which produce it; whilst living in small ill-ventilated, dark, and overcrowded dwellings is the most common cause of its acquirement. It is surely an interesting fact that I have observed the occurrence of scrofulous kinds of disease in animals under similar circumstances. I was obliged, it is true, to leave the question open whether inoculation in animals contributed essentially to visceral, skin, and bone affections or whether the external conditions alone were sufficient. Still, it is probable that the cutaneous puncture gave at least the impulse to the general changes, but whether really from resorption of detritus, or from simple setting up of inflammatory irritation, remains undecided.

I must pause here a little to consider the practically important question as to the hurtfulness of vaccination. Opponents of this measure maintain that besides other diseases it is especially scrofula which is transmitted by vaccination. According to my theory, scrofulosis is neither a contagious nor a specific disease; therefore, I emphatically deny the possibility of transmitting any scrofulous virus whatever from one individual to another. It is another matter if we ask whether vaccination is ever able to scrofulise a child which has been vaccinated indifferently from a scrofulous or a non-scrofulous vaccinifer. As the experiments on which my views rest are not yet concluded, and as very many doubts still remain, I do not wish my opinions to be accepted save with great reserve. I believe, then, that vaccination may be an exciting cause in bringing forth scrofulosis in children who already possess the inherited predisposition to the disease; but in this case any other sort of small wound, a trifling catarrh, &c., may have a similar action, and therefore vaccination cannot be singled out as the essential morbific agent. Indeed the most insignificant glandular swelling can remain quiescent and undergo caseation where the liability exists. It is also possible that vaccination gives the accidental impulse to the outbreak of scrofulosis, when the child lives amidst the external injurious influences which are wont to occasion the acquired disease. I have often seen children suffer a long time from

slight skin eruptions after vaccination, but these always completely vanished in the course of a few weeks; if they did not, there was evidence of a disposition to scrofulosis, either acquired or inherited from constitutionally diseased parents. Hence it is idle to talk of an essential perniciousness in vaccination, at least in comparison with the great benefits it confers.

One other point is worth mentioning. Although vaccina- tion with pure clear lymph is without any danger, yet the use of turbid lymph which contains corpuscular elements, i. e. pus and blood-cells, is perhaps not altogether beyond suspicion. Attention has been repeatedly drawn to this topic, and a warning sounded against such lymph. Whether or not those cases in which obstinate skin eruptions, slight disorders of weeks' duration, &c., have been observed to follow vaccination, were traceable to this cause, must be determined by more numerous investigations than I have been able to institute. It will therefore be seen that many knotty points remain to be unravelled.

3. HÆMOPTYSIS.-Up to the beginning of this century. no one had any doubt as to hæmoptysis being one of the most frequent causes of phthisis. This opinion, however, was abandoned by most men through the authority of Laennec, who maintained that where hæmoptysis apparently ushers in phthisis latent tubercles are then in existence, and that it is never the cause but always the consequence of an already present tuberculosis. It cannot be denied that he was led to these views principally from theoretical considerations. His doctrine that tubercle is a specific new formation was irreconcileable with hæmoptysis being a cause, and hence he had recourse to another interpretation, but no one can possibly assent to it whose observations are made in a candid and impartial spirit, uninfluenced by the bias of a foregone conclusion.

Our forefathers were excellent observers, and the experience they acquired deserves a much higher appreciation than some have thought proper to give it in recent times. They were not equipped with objective instruments for physical diagnosis, and were thrown back on subjective symp

toms solely; they had therefore a keener perceptivity than is possessed by those who often treat such symptoms as of subordinate importance in consequence of relying upon objective methods of investigation. Can any keen-eyed and impartial observer deny that many cases many cases of hæmoptysis occur suddenly in persons who are quite well? Why should it be here assumed for the sake of a theory that there must have existed a tuberculosis which was previously altogether unnoticed? I have often enough seen perfectly robust individuals who enjoyed sound health, or at least who manifested no abnormal condition, become suddenly attacked with hæmoptysis, whereupon all the symptoms of phthisis followed, and I could bring forward many striking proofs of the fact.

The following appears to me to explain the causal relation between hæmoptysis and phthisis. My experiments convinced me that fresh blood in the air-passages is able to set up inflammation of the pulmonary structures. The same thing occurs in man as well as in animals, numerous observations having convincingly proved that bronchitis and pneumonia are easily lighted up if blood flows down into the trachea after tracheotomy. Why, then, should we not venture to think that blood which gets into the lung without tracheotomy, but is directly effused there, can likewise act as an irritant and excite inflammation? Have we not observed dry cough, perhaps also dyspnoea, pyrexia, and all the symptoms of pneumonia, make their appearance a few days after most attacks of hæmoptysis? If we once admit that pneumonia can be produced by hæmoptysis, then the possibility of the pneumonical products undergoing caseation, followed by phthisis and tuberculosis, must be conceded.

I believe, therefore, that hæmoptysis may appear in a person perfectly healthy, and either be destitute of results, as I have often seen, or lead to bronchitis and circumscribed pneumonia. The products of the latter diseases become caseous and induce acute or chronic phthisis, with or without tuberculosis, especially in those who possess the phthisical habitus.* The question remains for the pre

* Here follows a case of Andral's illustrating the above remarks. It is the less necessary to reproduce it in this place, since clinical facts are rapidly accumulating in verification of the author's deductions.-G. M.

sent undecided as to the occurrence of true tuberculosis after hæmoptysis from the direct resorption of degenerated or shrivelled blood-corpuscles, without the intervention of caseous pneumonia. Yet, whilst regarding hæmoptysis as a cause of phthisis, it is perhaps scarcely necessary to add that I do not consider every hæmoptysis of phthisical persons as a primary affection; on the contrary, my opinion is that the most frequent attacks are not the causes, but the consequences of more or less advanced phthisis due to ulceration of the lung. But even secondary effusions of blood may, according to the modern point of view, lead to further pneumonical deposits and to fresh tubercular eruptions. Lastly, hæmoptysis may appear like epistaxis in persons of delicate constitution as an expression of the existing cachexia, and then be the forerunner of phthisis. In such cases hæmoptysis is, no doubt, an outcome of the phthisical habit, but afterwards the immediate cause of phthisis itself.

4. BRONCHITIS.-It is an undisputed fact that phthisis very frequently begins with the symptoms of simple bronchial catarrh, but it is questionable if the latter is always the result of existent tubercle, or of tubercle in course of formation as Laennec teaches. On this point I side with Laennec's opponents, who, whilst admitting that such symptoms are very frequently caused by phthisis and tuberculosis, also hold that a simple bronchitis excited, for instance, by catching cold, may end in phthisis, especially where the liability is present. Laennec's views are based on the theory that tubercle is a specific new formation. The reasons for this theory, which is contradicted by impartial observation, fall to the ground along with the theory itself. When a case presents bronchitic symptoms without alteration of the percussion note, I contend that simple bronchitis only exists; whereas, according to the other theory, latent tubercles not yet discoverable by physical examination must be present. Neither of us, it is true, can bring forward positive evidence in support of our respective views, nor does the conflict of opinion between us admit of adjustment, but it will be conceded that he places an arbitrary interpretation on the