said with regard to this subject, is upon a very precarious footing." "I have just to say, what I would wish you to take along with you, that we know extremely little with regard to the mixture (composition) of animal fluids; and that whenever we apply our suppositions to the different ingredients, or their different proportions, it is purely hypothetical."

In taking a review of the morbid conditions of the fluids, recognised by pathologists under the names of Spissitude, Tenuity, and Acrimony, Dr Cullen stated the grounds of his belief, that the doctrines of the humoral pathology, then prevailing, were not available in medical science.

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"I have," says he, in speaking of Spissitude, "endeavoured to shew that the actual occurrence of this state is uncertain, and that the means by which it can be produced are equally so. Therefore it will appear that the doctrine of Lentor, which rests upon that of spissitude, is upon the most uncertain foundation. When I first became acquainted with physic, I found that physicians reasoned boldly on this matter. They spoke of thickening or thinning the blood with as much confidence as a Scotch maid would speak of making porridge thicker or thinner. There is a possibility of the deviation of the blood towards spissitude, but it is both uncertain what causes can produce it, and to what degree it can be carried. Probably there are powers in the economy that serve to balance all the several causes of it, (such as the diminution of the secretions, and the inviscating of the more fluid parts,) which are means of preventing a morbid spissitude from occurring in the body." And in respect of the opposite condition of the blood, Tenuity, he remarked: "When we perceive increased secretions and hydropic effusions taking place, we must not refer them always to the tenuity of the blood, for in most instances they depend upon some change in the state of the secretory organs, or in the state

of the excretories; and, I say, there are fifty cases in which dropsy depends upon a certain condition of the exhalents and absorbents, for one in which it depends upon this change in the state of the blood."

The doctrine of Acrimonies, the fallacies of which Vacca takes to himself great credit for having exposed in his treatise, entitled "Pensieri intorno a vari soggetti di Medicina Fisica," published some years before 1787, is a subject which Dr Cullen had, many years before that time, discussed in his Lectures on the Theory of Physic, in the following terms :-" What and how many are the several deviations from a sound state which may occur in the fluids, is what we are but little acquainted with. The most remarkable circumstance is the case of Acrimony. We call those bodies acrids which, applied to our sensible parts, give pain, or which stimulate the moving fibres into contraction, but the mechanical operation of which we cannot discern." "It is only the chemical acrimony taking place in our fluids that we are to attend to here. I will limit the subject still farther. From our having no distinct notion of any other chemical action but that of the saline, I would say that it is saline matters present in our blood in uncommon quantity, and of an uncommon quality, that we are here (i. e., under the title of the Acrimonies of the Fluids) seeking after." "Gaubius is one of those who suppose that acid acrimony may be carried along into the mass of blood; but this to me is disputable. I have shewn that there is a quantity of acid constantly present in the prima viæ; but as no deviation from health arises from this, I conclude that there is a provision in nature for covering (neutralising) it; and there is no experiment that has ever shewed the existence of it in its separate (free) state in the mass of blood. That it is materially present there, we allow, and that distillation can obtain it from thence, is true. There is, indeed, some suspicion of its appearing in secreted fluids,

but this is no proof of its being in the blood, and even this is still upon a very doubtful foundation." On the subject of alkalescent acrimony, Dr Cullen remarked in reference to the 310th paragraph of Gaubius: "I must begin here with doubting the fact, if ever this kind of acrimony does exist in the fluids. I shall shew just now that the causes of it are not sufficiently obvious; and if it does exist, it is in consequence of the animal substance being dissolved; it is in consequence of a putrefaction, which never takes place in living bodies because, before it arrives to that degree, it affects the nervous power, and induces death." "That a fixed alkali ever gets at the mass of blood to decompose our ammoniacal salt, from many considerations I could render very doubtful." "Gaubius is, I believe, the only person who imagines that such an acrimony can prevail or subsist in the fluids." In proceeding to comment on the 312th paragraph of Gaubius, in which that author considers Putredo, Dr Cullen remarks; "We justly suppose the putrescent state to be an alkalescent state." "But here is a very imperfect doctrine with regard to putrefaction. Gaubius throws in a great many facts, but since he wrote this (and there is no great difference in the present from what he said in the first edition), a prodigious change has been made in the state of our science, with regard to putrefaction, as you will see in the writings of Sir John Pringle, who laid the foundation, and of a Lady, who has written sur la Putrefaction;1 and more especially you will find the subject treated in the Dijon prize-dissertations sur les Antiseptiques." I have not collected the import of the whole that has been said on this subject, as I cannot make out any

1 Essai pour servir à l'Histoire de la Putrefaction. 8vo. Paris,

1776.

2 Boissieu, Bordenave and Godard, sur les Antiseptiques. 8vo. Dijon, 1769.

consistent theory with regard to it; and you must, at your leisure, take the facts and make a cautious use of them."1

6.

Dr Cullen was accustomed to wind up his review of the doctrine of Acrimony of the humors, as expounded by Gaubius, in the following terms: Gaubius has promised that he was to explain the different species of acrimony, but you see what it amounts to,-a very doubtful supposition with regard to an acid entering the mass of blood, and of a volatile alkali present there, &c.; and it is evident that we know only of the presence of a neutral, and that we still know nothing of any other."

Before quitting the subject of the Pathology of the Fluids, it may be remarked, that Dr Cullen fully understood that we are not at liberty to draw inferences respecting the changes which particular agents, introduced into the living economy, will induce on the circulating blood, from what we observe these agents to occasion when brought into contact with it, out of the

1 The following passage from the same lectures, seems deserving of being quoted here, as recognising the inaccuracy of an opinion that was inadvertently admitted by Dr Cullen into the definition of Scurvy given in his Nosology, and which definition has, incautiously as I think, been referred to by a distinguished pathologist and practitioner, as shewing the uselessness of Nosology. "There is no doubt, that if either the urine, or the perspiration by which the ammoniacal salts are thrown out of the body be diminished, a quantity of these salts will remain; and we know, in the case of the Scurvy, that it is always assisted or increased by a suppression of perspiration. This has, indeed, been pushed to excess, by a late writer, who alleges that no scurvy is produced in the warm climates where the perspiration is kept up; but there are facts to the contrary; facts which prove that in the middle of the torrid zone, a saline putrescent animal diet will give the scurvy, though not so readily as in the colder climates, or in the same degree."

body. The illustration which he gives of this fact, whatever may be thought of his mode of explaining it, is interesting and important in itself; and, so far as I am aware, original.

"With regard to the Spirituosa," says he, "I have a curious observation to make. Alcohol applied to our blood does coagulate it; but this coagulation never takes place in the living body, because alcohol, when diluted to a certain degree, does not shew its powers in that way, and it cannot be introduced by the mouth into our fluids, without receiving such dilution. But we have instances of persons who take spirits in extraordinary quantity; and one would expect that among them we would find the blood coagulated; but on the contrary, their blood is of a remarkable fluidity. All our drunkards, male and female, particularly those who have dealt in brandy, have their blood more fluid than natural, and are liable to hæmorrhages; and I never knew a woman who was a drunkard, but she continued her menstruation longer than the ordinary period of life, even to 60 years of age; or, if it had gone away, it returned so late as that period and flowed again. I have not been extremely troubled in practice with cases of abundant menstruation; but towards the decline of life it is an accident that does happen, and it has occurred three times in such women as drank spirits, for once in those that did not, so that we are mistaken in our reasonings, in this respect; and this effect is not owing to the spirit acting upon the mass of blood, but to its acting upon the nervous system."

3. The Brunonian canon, that the action of all the powers which operate upon the animal economy, whether with a noxious or with a salutary effect, is stimulant, was assailed in Italy upon various grounds. In the first place, it was maintained that there is a class of substances which exert upon this economy, directly and positively, an action quite the reverse of stimulant,

VOL. II.

2 B