On detaching the placenta carefully from the uterus, the deciduous membrane is found to adhere so closely to the umbilical vessels which it covers, that it is impossible to remove it without tearing these vessels. With the fibres uniting the placental decidua to the uterus are mingled numerous small blood-vessels, proceeding from the inner membrane of the uterus to the decidua; and these vessels, though more numerous at the connexion of the placenta with the uterus, exist universally throughout the whole extent of the membrane. There is no vestige of the passage of any great blood-vessel, either artery or vein, through the intervening decidua, from the uterus to the placenta; nor has the appearance of the orifice of a vessel been discovered, even with the help of a magnifier, on the uterine surface of the placenta. This surface of the placenta deprived of the deciduous membrane presents a mass of floating vessels, its texture being extremely soft and easily torn; and no cells are discernible in its structure, by the minutest examination.

At that part of the surface of the uterus to which the placenta has been adherent, there are observable a great number of openings leading obliquely through the inner membrane of the uterus, and large enough to admit the point of the little finger: their edges are perfectly smooth, and present not the slightest appearance of having been lacerated by the removal of the placenta. In some places they have a semilunar or elliptical form, and in others they resemble a double valvular aperture. Over these openings in the inner membrane of the uterus, the placenta, covered by deciduous membrane, is directly applied, and closes them in such a manner that the maternal blood, as it flows in the uterine sinuses, cannot possibly escape either into the cavity of the uterus, or into the substance of the placenta. The above appearances on the inner surface of the uterus have been accurately represented by RŒDERER; from whose work fig. 1. of Plate I. is taken.

When air is forcibly thrown either into the spermatic arteries or veins, the whole inner membrane of the uterus is

raised by it; but none of the air passes across the deciduous membrane into the placenta, nor does it escape from the semilunar openings in the inner membrane of the uterus, until the attachment of the deciduous membrane to the uterus is destroyed. There are no openings in the deciduous membrane corresponding with these valvular apertures now described, in the internal membrane of the uterus. The uterine surface of the placenta is accurately represented in fig. 2. Plate I.

If a placenta be examined which has recently been separated from the uterus in natural labour, without any artificial force having been employed, its surface will be found uniformly smooth, and covered with the deciduous membrane; which could not be the case, did any large vessels connect it with the uterus. The placenta in a great majority of cases is also detached from the uterus after labour, with the least imaginable force; which would be impossible if a union by large blood-vessels, possessing the ordinary strength of arteries and veins, actually existed. Besides, a vascular connexion of such a kind would be likely to give rise, in every case, to dangerous hemorrhage subsequent to parturition, a circumstance not in accordance with daily experience."

The following observations are offered by our author as reasons why his predecessors have fallen into error in their anatomical researches.

"NOORTWYCH, REDERER, HAller, Dr. W. and Mr. J. HUNTER, and Dr. DONALD MONRO, do not appear to have examined the gravid uterus and its contents in the natural state of the parts, but after fluids had been forcibly injected into the hypogastric and spermatic arteries. The laceration of the deciduous membrane covering the orifices of the uterine sinuses followed this artificial process, as well as the formation of deposits of injection in the vascular structure of the placenta, giving rise to the deceptive appearance of cells. That this took place in the examinations made by REDERER* and MONRO†, does

* Icones Uteri humani, Observationibus illustratæ. J. G. REDERER, 1759. † Essays and Observations, Physical

not admit of dispute; and the following facts render it more than probable that the HUNTERS were also misled, by the effects of artificial distension of the placenta, from the extravasation of the fluids forced into the uterine vessels.

In the course of last autumn, the preparations of the gravid uterus in the Hunterian Museum at Glasgow were examined at my request by Dr. NIMMO; and in none of them does it appear certain that any great blood-vessels pass from the uterus into cells in the placenta; but in many the deposits of injection, causing the appearance of cells, were observed evidently to be the result of extravasation. No preparation in the collection seems to have been expressly made for the purpose of proving or disproving the fact that the deciduous membrane passes over the uterine surface of the placenta; but in reference to preparation R. R. No. 139, it is observed by Dr. NIMMO that no vascular openings are visible in the membrane interposed between the uterus and pla

R. R. 121, is described in the printed Catalogue as follows: A small portion of placenta and uterus, where the cells of the placenta have been injected from the veins of the uterus. The veins are seen very large, entering the substance of the placenta.'

Dr. NIMMO makes the following observations on this specimen: "This preparation seems to be most in point. I would describe it differently. The cellular substance of the placenta has certainly been filled from the uterine vessels. These, however, instead of passing directly into the placenta, are distinctly seen applying their open mouths to the membrane of the placenta, where the injection in some instances stops. The membrane is thinner here than where no vessels are applied, consisting, so to describe it, of one layer, while a second layer covers all other parts. Where the injection has passed into the substance of the placenta, it has evidently been forced to the side between the layers, and found some weak point, whereby it has entered into and been diffused throughout the cellular texture of the placenta.*'

From the foregoing facts, our author thinks he may safely conclude that the human placenta does not consist of two parts, maternal and fœtal-that no cells exist in its substance-and that there is no communication between the uterus and placenta by large arteries and veins. The whole blood sent to the uterus by the spermatic and hypogastric arteries, (except the small portion supplied to its parietes and to the membrana decidua by the inner membrane of the uterus) flows into the uterine veins or sinuses, and, after circulating through them, is returned into the general circulation of the mother by the spermatic and hypo

My friend SAMUEL BROUGHTON, Esq. F.R.S., during a recent visit to the Hunterian Museum at Glasgow, exexamined the preparations of the placenta and uterus at my request, and authorizes me to say that his observa

NIMMO's statements.

gastric veins, without entering the substance of the placenta.

"The deciduous membrane being interposed between the umbilical vessels and the uterus, whatever changes take place in the foetal blood, must result from the indirect exposure of this fluid, as it circulates through the placenta, to the maternal blood flowing in the great uterine sinuses."

There is appended to the paper a valuable communication from Mr. Owen respecting the anatomy of the uterus and placenta, and the whole is illus trated by two expressive plates.

XXI.

OBSERVATIONS ON VARIOUS DISEASES.

By ROBERT J. GRAVES, M.D.

UNDER this head, Dr. G. has communicated, through the medium of our Dublin cotemporary (No. II.), some facts, elucidatory of the nature of diseases and the operation of remedies. The observations are practical, and not speculative.

1. Ptyalism. This was a case of profuse secretion of saliva, independent of mercury. The patient (a female) first had leucorrhoea, which suddenly ceased, and was succeeded by anasarca. This disappearing under proper remedies, was followed by gastric irritation; upon the disappearance of which a profuse ptyalism ensued, which resisted purgatives, tonics, gargles, and various other remedies.

"In twenty-four hours she spits more than a pint and a half of fluid, consisting of a whitish, viscid mucus, secreted by the mucous membrane of the fauces and back of the pharynx, from whence it is thrown into the mouth by a hawking, renewed every two or three minutes, with scarcely any interruption either during the night or day, and rendering the patient truly miserable from want of sleep. The throat and fauces are pale, and their soft parts extremely flabby and relaxed, although there is a constant irritation in the throat in consequence of the presence of an unna

tural quantity of mucus, yet no soreness is felt, neither do the parts appear inflamed. The salivary glands are not concerned in the disease, and do not secrete more than the usual quantity of fluid. Her appetite is very bad, her skin dry, and she has a haggard, emaciated countenance.

The well-known good effects of opium in several diseases of increased secretion, diabetes, diarrhoea, and certain forms of dropsy, suggested to me the trial of this medicine in the apparently almost hopeless case I have related, and I accordingly ordered the patient one grain of opium every fourth bour. On the following day, she returned to inform me that she had slept during the whole night, and on awaking had no return of the spitting. Her joy was great, and she and her friends considered the effect of the pills, in thus suddenly stopping the spitting, as most extraordinary; and I must confess, that my surprise was almost equal to their's.

She then told me, that several medical students who lived in her house, and who had witnessed the previous violence and obstinacy of her complaint, had been so much struck by its sudden cessation under the influence of the pills, that she was commissioned by them to inquire what I ordered. I mention this circumstance, to shew how very remarkable was the benefit she received from the opium. The pills were continued for some days, when the quantity of opium was augmented on account of some recurrence of the spitting; unfortunately they induced constipation of bowels, and, consequently, she has been frequently obliged to leave them off, but she is, on the whole, much improved in health, and although she is still subject to the disease, its severity is comparatively trifling, and it uniformly disappears almost entirely when she recurs to the use of opium. She visited me this day, the 18th of March. In connexion with this subject I may observe, that a lady, a patient of mine, who took a large quantity of mercury many years ago, has been ever since subject to occasional returns of salivation, in every respect resembling that produced by

mercury. During these fits, which are always brought on by exposure to cold, the mouth is sore; the gums red and swollen; the salivation copious, and the breath is strongly impregnated with the mercurial fetor. Several such cases have been recorded by others, and are extremely instructive, proving that the deleterious effects of mercury on the system may lie long dormant, and be afterwards suddenly called into action by various causes. In this way we may explain the attacks of periostitis, to which persons who have been mercurialized, are often liable for years, upon exposure to cold. Formerly such attacks were indiscriminately attributed to a remnant of the syphilitic taint, but I have witnessed the same occur rence in persons who had no syphilitic disease, and who had taken mercury for other complaints. One of the most violent attacks of periostitis I ever witnessed, followed salivation in a lady to whom mercury had been given several months before, for the cure of peritonitis. To conclude, I have seen many cases totally at variance with the assertion of Ballingall and others, that the secondary symptoms, attributed by recent authors to mercury, are owing to lues; not being observed, as they state, except in cases where that medium had been exhibited for the cure of the venereal disease. The venereal poison produces a peculiar train of primary and secondary symptoms. The mercurial another, and that not very dissimilar. Experience has proved, that in general the venereal symptoms yield to the action of mercury, but occasionally this is not the case, in consequence either of some constitutional peculiarity, or an injudicious use of this mineral, and thus the constitution labours under a modified disease, resulting from the combined effects of the two poisons. Attention to the effects of the remedy in the first instance, will generally prevent the occurrence of so disastrous a complication. My own experience has convinced me, that the majority of venereal cases may be cured by the non-mercurial plan of treatment; but whenever the disease, whether primary or secondary, proves more

than usually obstinate, the practitioner should then have recourse to mercury; the previous treatment will render its curative influence at once safer and more energetic."

2. Cold Affusion in Convulsions. This remedy in the convulsions of children has not attracted much attention. Dr. Graves, having witnessed the good effects of the remedy, appears to have followed up the practice. The following case he offers as an example. A young gentleman, nine years of age, was convalescing from scarlatina, when anasarca, and afterwards convulsions, occurred. The fits were very violent, and the youth appeared moribund, his eyes being distorted, void of expression, and fixed-face cadaverous-extremities cold-pulse feeble, and 150.

"In addition, he appeared to be nearly destitute of muscular power, and in the interval between the fits was unable to speak, while a loud tracheal râle seemed to announce the near approach of death. As I have detailed the symptoms of the case with the most scrupulous fidelity, and without the least exaggeration, I need scarcely add, that our patient's case appeared utterly hopeless. Our first step was to place him in the arms of a strong nurse-tender, who maintained him as nearly as possible in the sitting posture; our object in this was to relieve the lungs, and diminish the cerebral congestion. Those who have watched over the dying, are aware that the final struggle may be often much protracted, by frequently changing the patient's position in bed, and particularly by avoiding the horizontal posture. This mode of proceeding, by preventing the gravitation of the blood to any one part of the lungs, and by counteracting the accumulation of mucus in any particular portion of the bronchial tubes, causes both to remain for a longer time pervious to the air, and favours the last efforts of the respiratory apparatus. We next proceeded to pour a small stream of cold water from a kettle on his head, the effects were extremely satisfactory, for in a short time the eyes assumed a more natural appearance, and lost the spas

modic fixedness, while the pulse became more and more distinct, and diminished in frequency; in short the violence of the fit soon subsided, he was able to expectorate the mucus which had clogged the larger air-passages, and had caused the rattles, and in the course of half an hour a very marked improvement was perceptible, the patient being then able to speak and swallow. The convulsions, however, returned several times during the ensuing day, but at each recurrence, their duration was lessened, and their violence diminished by the cold affusion. Sitting by the bed of this patient, I more than once was able to predict the immediate adproach of the fit, by means of watching the pulsation of the carotids, which then became much more frequent and stronger. This observation, in connexion with the fact, that the pulse at the wrist became weaker and more indistinct at that very moment, suggests many interesting considerations concerning local determinations of blood.

It is almost unnecessary to remark, that the time we had so unexpectedly gained was not spent in inaction, and that we immediately had recourse to various other active remedies, such as leeching the neck, purgative injections, and mercurials, administered both internally and externally, with a view of affecting the mouth rapidly. In addition to the modes of applying mercury usually employed, I can recommend the application of the ointment to the armpits; this alone will frequently affect the mouth in a few days. The motions of the patient's arms here perform the office of friction, and this part of the skin seems to possess very active absorbing, as well as exhaling powers, and is likewise more protected from the contact of the clothes, &c., so that the ointment is less easily wiped off and wasted. With regard to local detraction of blood where there is determi

"No bronchitis or pectoral affection was present, and consequently the tracheal rále (rattles) was of the most ominous import."

nation to the head, experience has taught me, that in no case ought we to apply leeches to the temples. This is a very important observation, and applies to the treatment of various cerebral affections, such as occur in fever apoplexy, paralysis, hydrocephalus, &c. Leeching the temples in such cases, not unfrequently aggravates the cerebral symptoms, whereas, if the leeches are applied behind the ear, or what is still better, along one side of the neck, this untoward event will be avoided. I say along one side of the neck, because we are thus enabled to promote the flow of blood where the leeches fall off, with less annoyance to the patient than if leeches had been applied at both sides. A most instructive monograph might be written on the application of cold to the head in various diseases; at present, much mischief frequently arises from practitioners being unacquainted with the different degrees of cold suitable to different states of the cerebral organ, and the different methods of conducting its application, so as to produce relief. In one case of fever, I saw violent mania immediately follow the injudicious application of ice to the head; and in another, much difficulty was experienced in saving the life of a young person, in whom a collapse of the system, without relief of the local affection, had been induced by the too copious and continued application of cold water to the head. Where very violent pain in the head occurs in fever, the cold dashing with water from a height, as recommended by Dr. Smith in his excellent treatise, is often a most valuable remedy, but in convulsive diseases, like that now described, this application is too violent; in such cases, the stream of water should be small, not poured from a height, and should be discontinued the moment the fit ceases, to be again renewed on the approach of another paroxysm. I am informed by an eminent practitioner of this city, that he twice witnessed fatal convulsions follow the injudicious use of cold affusion in mania. The efficacy of cold affusion in delirium tremens, in asphyxia, in cases of over