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most brilliant enterprises. All their own historians deplore the effects of this apathy, this fatal recklessness, which has almost always kept them dependent on the industry of their neighbours, or at least

behind them in improvement. The happiest ages of their monarchy have not been exempted from this evil, which seems to be as much the product of the climate as of the administration.

NATURAL

NATURAL HISTORY.

Account of the Dissection of a Human Foetus, in which the Circulation of the Blood was carried on without a Heart. By Mr. B. C. Brodie. [From the Philosophical Transactions of the Royal Society of London, for 1809.]

A

N opportunity lately occurred to me of examining a human fœtus, in which the heart was wanting, and the circulation of the blood was carried on by the action of the vessels only. There have been some other instances of this remarkable deviation from the natural structure; but in that to which I allude, the growth of the child had been natural, and it differed much less from the natural formation than in any of those which are on record, and I have therefore been induced to draw up the following account of it.

A woman was delivered of twins in the beginning of the seventh month of pregnancy. There was a placenta with two umbilical chords, which had their origin about three inches distant from each other. The placenta was not preserved, but Mr. Adams, who attended the mother in her lying. in, observed nothing unusual in its

appearance. Both fœtuses were born dead. They were nearly of the same size. One of them in no respect differed from the ordinary formation; the other had an unusual appearance, and Mr. Adams thought it deserving of examination. Through Dr. Hooper it was put into my hands for this pur

pose.

The fœtus measured thirteen inches from the summit of the cranium to the feet. The thorax and abdomen were surrounded by a large shapeless mass, which concealed the form of the whole upper part of the body. This mass proved to be the integuments covering the posterior part of the neck and thorax, distended with a watery fluid, about three pints in quantity, contained in two cysts, lined by a smooth membrane. When the fluid was evacuated, and the cysts allowed to collapse, the foetus had nearly the natural form. Its extremities had nearly the usual appearance, except that on the right hand there was no thumb; on the left hand there was no thumb also, and only a single finger. There were three toes on the right foot, and four toes on the left foot. The external nostrils consisted only of two folds of

skin, under each of which was the orifice of an internal nostril, but pervious only for about half an inch. There was a hare-lip, and a cleft in the bony palate, extending one third of an inch backwards.

On dissection the cranium was found somewhat compressed by the fluid contained in the cyst behind it. The brain itself was too putrid for accurate examination, but it was of nearly the natural size, and nothing unusual was observed in it. The membranes had the natural appearance, and the nerves appeared to go off from the brain and spinal marrow nearly as

usual.

In the thorax there was no heart, thymus gland, or pleura. The trachea was situated immediately behind the sternum. It had its natural appearance, and divided as usual into the two bronchia. The latter terminated in the lungs, which consisted of two rounded bodies, not more than onethird of an inch in diameter, having a smooth external surface, and composed internally of a dense cellular substance. The oesophagus had the usual situation, but it terminated in a cul-de-sac at the lower part of the thorax. The rest of the thorax was filled with a dense cellular substance; and in place of the diaphragm, there was a membranous septum between it and the cavity of the abdomen.

In the abdomen, the stomach had no cardiac orifice. The intestine was attached to the mesentery in the usual way; but it was proportionably shorter than natural. There was an imperfect cæcum, but the colon not distinguished by any difference of structure or appearance from the rest of

the intestine. The rectum had its usual situation in the pelvis. The spleen and renal capsules were small; the kidneys, bladder, penis, and testicles, had the usual appearance. The abdomen was lined by peritoneum, but there was no omentum. The liver and gallbladder were wanting.

As there was no heart, it became an object of importance to ascertain the exact nature of the circulation: for this purpose the bloodvessels were traced with attention.

The umbilical chord consisted of two vessels only: one of these was larger than the other, and its coats resembled those of a vein, while those of the smaller vessel were thick and elastic, like those of an artery. Both of these vessels entered the navel of the child. The artery passed to the left groin by the side of the urachus, occupying the usual situation of the left umbilical artery. Here it gave off the external and internal iliac arteries of the left side, and was then continued upwards on the fore part of the spine forming the aorta. From the aorta arose the common trunk of the right iliac artery, and the branches to the viscera and parietes of the thorax and abdomen. At the upper part of the thorax, it sent off the two subclavian, and afterwards divided into the two carotid arteries, without forming an arch. The veins corresponding to these arteries terminated in the vena cava, which was situated on the anterior part of the spine before the aorta, and passed downwards before the right kidney to the right groin. Here it became reflected upwards by the side of the urachus to the navel, and was

continued

continued into the larger vessel or vein of the chord.

It appears, therefore, that in this fœtus not only the heart was wanting, but there was no commu. nication of any kind between the trunks of the venous and arterial systems, as in the natural fœtus, where there is a heart. The only communication between the two sets of vessels, was by means of the capillary branches anastomosing as usual in the fœtus, and in the placenta. The blood must have been propelled from the placenta to the child, through the artery of the chord, and must have been returned to the placenta by means of the vein, so that the placenta must have been at once the source and the termination of the circulation, and the blood must have been propelled by the action of the vessels only.

It is to be understood, that the circulation in the fœtus receives no propelling power from the action of the heart and arteries of the mother. This, although perfectly known to anatomists, it is proper to mention, as it may not be equally known to all the members of this society.

It appears extraordinary, that under these circumstances, notwith. standing the circulation through the placenta must have been more languid than is natural,thatorganshould nevertheless have been capable of exercising its proper functions, so as to produce those changes on the blood, which are necessary for the maintenance of fœtal life. This may be explained by considering that in the natural fœtus the umbilical arteries are branches of the

general arterial system, and only a portion of the blood of the child is sent to the placenta, whereas in the fœtus which I have described, the trunk of the vena cava was continued into the vein of the chord, and the whole of the venous blood circulated through the placenta, and was exposed to the influence of the arterial blood of the mother.

But the most interesting circumstance which we learn from this examination is, that the circulation not only can be carried on without a heart, but that a child so circumstanced can be maintained in its growth, so as to attain the same size as a foetus which is possessed of that organ. This fact is contrary to what prior experience has led us to expect, as will appear from the following abstract of the authenticated cases of this species of malformation, which we find on record.

A monster, in which there was no heart, is described by M. Mery. There were twins, one of which was well-formed, and of the usual size of a six months' child; the size of the other was not mentioned, so that no comparison could be made between them. In the latter, the head, neck, and other extremities were wanting. There were no vestiges of a brain, nor was there any liver. The dissection of the blood vessels does not appear to have been very accurately made, but, from the general account, I should suppose that the circulation did not materially differ from that of the foetus which I have described.

• Histoire de l'Academie Royale des Sciences, 1720.

Another

Another instance of this kind is described by M. Winslow.* This was also a twin, only seven inches in length. The age and size of the other child are not mentioned. In this instance there was no head, nor any vestige of brain. There were no lungs, liver, stomach, nor spleen, and only a small portion of intestine. The arterial system is described as being complete, communicating with the placenta by the umbilical vein opening into the aorta, and the umbilical arteries arising nearly as usual. In this instance there was a circle of vessels formed by the arteries only, for M. Winslow expressly states, that there were no veins; and however extraordinary this may appear, we cannot be otherwise than cautious in denying an observation made by an anatomist so remarkable for his extreme accuracy and minute

ness.

Dr. le Cat, of Rouen, states another case of twins + born at the end of the ninth month of pregnancy. One of them was a well-formed child, of the usual size, but the other was only twelve inches and a half in length. The head of the latter was very imperfect, and there was only a very minute portion of brain. The heart, lungs, liver, stomach, and spleen, were entirely wanting, and there was only a small portion of intestine. The arterial system was perfect: the umbilical veinterminated in the aorta, and the umbilical arteries had their origin from the internal iliac, as usual.. There is, however, an obscurity in the account of the circulation, as it

is stated that there were veins, but they were not traced, nor was any communication made out between them and the arteries, or the vessels of the chord.

Dr. Clarket has given an account of a case, in which a woman, after a natural labour, was delivered of a healthy child, and also of a substance covered by common integuments, of an oval form, four inches in length, and having a separate navel-string and placenta. In this substance there was one os innominatum, with a femur, tibia, and fibula. There were neither brain nor nerves; nor were there any viscera, except a small portion of intestine. The umbilical chord consisted of two vessels, an artery and a vein, both of which ramified in this substance and in the placenta.

In Dr. Hunter's anatomical collection, there are two specimens of monsters born without hearts. In both of them the whole upper part of the body was wanting; and in neither was the exact nature of the circulation ascertained.

In each of the instances which I have quoted, not only the heart was wanting, but the fœtus in other respects was so imperfect, that it could not be considered as any thing more than a mola, or an irregularly-formed living mass connected with the placenta. In particular, in all of them the brain, which may with justice be considered as affording the best distinction between a mola and a fœtus, was wanting; whereas in that which forms the subject of the present paper, the brain was nearly as large

* Histoire de l'Academie Royale des Sciences, 1740. + Phil. Trans. for 1767.

Phil. Trans. for 1793.

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