ON THE PHYSIOLOGY OF THE LACTEAL SYSTEM.

469 This case seems conclusive upon the matter, for if Mr. Wood, all parts of the body, and if the pressure were not less in the entirely abstaining from all liquids, except such as were used in auricle than in any other vessel or cell of the body, their conthe formation of his boiled puddings, or were imbibed by them tained fluids could not return into its cavity. All the fluids of during cooking, voided a pint and a half of urine daily, it may be the circulation, in passing through their various channels from conceded that the urine of a person suffering from diabetes the cavity of the ventricle round to that of the auricle, are passing mellitus may much exceed the amount of liquids drank, when we from the greatest pressure to the least. In passing from the consider the very large quantity of cooked food of all kinds he heart, all fluids are passing from a greater pressure to a less; in takes during the day. passing to the heart, all fluids are passing from a greater pressure April,

1845.

ON THE PHYSIOLOGY OF THE LACTEAL SYSTEM. By E. L. BRYAN, Esq. Surgeon, Hoxton. THE distinguished Muller states, in his well-known and excellent work on Physiology-" I confess that the act of absorption in other parts, as well as in the intestines, is to me quite an enigma." And again: "The powers by which the lymph and chyle are moved are unknown." When I first entered upon medical studies, the perusal of the standard works on anatomy and physiology &c. which were placed in my hands, at once forced upon my mind the fact, that the profession had, age after age, pursued those sciences without having previously made themselves acquainted with the principles of physics-that is, had come to the study of organic matter in almost total ignorance of those laws which govern inorganic matter; had come to the investigation of the intricate machine, the human frame, without previously acquiring that knowledge which alone could enable them to understand even its simplest phenomena. It would have been amusing, had it not been painful, to observe the physiologist complacently persuading himself that in the study of living structures his mind was superior to the consideration of the principles of physic. Yet, while rapt in this conceit, he has been, from first to last, most eminently mechanical in his ideas of life, blundering on continually, and introducing explanations and expositions which are in accordance with no laws of physics, but are both mechanical and false. The details of the various experiments made to determine certain mechanical questions relating to the phenomena of the circulation, respiration, the movements and sounds of the heart, &c., are, with few exceptions, examples of an almost total want of such practical and well-digested knowledge of physical science as alone would enable the experimentalist to draw correct conclusions. These experiments, too, have almost all been unnecessary-no more required than the measuring a triangle by going over its whole surface inch by inch, instead of calculating It is, however, gratifyone side and two angles given. by the ing to perceive, that the certain sciences are more cultivated by the medical student than heretofore: they ought to form the groundwork of medical and surgical education: he who is well acquainted with them readily perceives how far they will apply to the various phenomena occurring in living beings, and it is he, and he alone, who gives no undue weight, no undue importance, to them. The result of their neglect has been, that of the whole mass of medical and surgical literature, nineteentwentieths are pure inanity, or worse-obstructions and stumblingblocks in the path of science. The intent of this paper is to explain familiarly that which Miiller could not understand-viz., absorption by lymphatics ’, and lacteals: an analysis of the phenomenon involves a consideration of I

a less. For elucidation, let the black lines of the following diagram represent the shortest circuit which the blood takes-namely, from the ventricle through the arteries, the capillaries, and the veins, into the auricle. The fluid leaves the ventricle (4) and enters the arteries, (3,) because the pressure is less in the arteries than in the ventricles; it leaves the arteries to enter the capillaries, (2,) because the pressure is less in those vessels than in the arteries ; from the capillaries (2) it passes into the veins, (1,) and from the veins it passes into the auricle, (0,) for the same reasons. The blood and other fluids do not move from a vital cause-they move because they are moved. The physiologist has perplexed himself by confounding vital and mechanical powers together. The blood, containing all the constituents of the body, is distributed, by the force of the ventricles, through the arteries, to all parts of the frame; it is received into the capillaries, where, in a state of minute division, it is brought under the influence of the nerves of organic life. In these vessels, according to the structure or mechanism of the organ supplied, a separation of certain constituents of the blood takes place-new combinations of its elements are formed. But the power which produces these changes is not what is called a mechanical power,-it is an atomic force, and does not affect the motion of the blood, considered as a mass. The fluid passes forward from the greater pressure to the less, until some local attraction arrests its atoms and fixes them, to add to, or to form, a tissue, and when these atoms are For further elucidaworn out, they fall into the current again. tion, let the dotted lines represent a longer course, and more minute vessels-say a vessel secreting lymph into a cell of the cellular tissue, with a lymphatic opening into the cell, and leading into the vena cava. In this case, a portion of the blood leaves the capillaries, and enters the cell. Now, the fluid enters this cell with a certain force; it distends this cell with a certain force; and as there exists a vessel leading to the right auricle, this same force induces the fluid to pass on towards the auricle that is to pass from a greater pressure to a less, with a current, slower than that of the shorter circuit, it is true, but still by the same mechanical force, that derived from the ventricle.

to

THE FORCES OF TIIE GENERAL CIRCULATION.

There is one primary and essential source of motion to the I fluids of the human bodv-tlje heart: its influence is universal I, ’, throughout the frame, and constant. In addition to this primary and essential source of motion, , there exist certain accessory forces, which are local in their influence, and are alternatelv assistant and obstructive, and ’i which result from the peristaltic action of the intestines, from I the movements of respiration, and from the exercise of the voluntary muscles. These forces are intrinsic, belonging to the machinery of the frame itself: but there is an extrinsic force, producing what is most improperly called absorption, and arising from those purely physical causes which occasion the phenomenon named ’ solution. All the fluids of the circulation are passing from the heart, or passing towards it. The cavity of the heart,whence the blood departs, affords an example of the greatest pressure which the blood sustains; the cavity of the auricle, which receives fluid from all parts of the body, offers an example of the least pressure which those fluids sustain. The ventricle injects with fluid every vessel, cell, and cavity of the body, and if its compression of its contained fluid were not greater than that of any other vessel, cell, or cavity of the body, the circulation could not go on in such vessel, cell, or cavity. The auricle receives fluid from

All vessels, cells, and cavities, (which are merely large cells,) filled by different constituents of the blood, are injected by the ventricles, through the medium of the arteries, by a certain force, and that same force is ready, when a channel exists, to carry the fluid on to the auricle, or else to an excretory duct, if its vessels lead into one. In fact, the whole case lies in this-that every vessel, every cell, every cavity of the body. has its connexion with the ventricle, on the one hand, and with the auricle on the other; and these vessels, cells, and cavities, are mere communications, more or less direct, between the cavity of the left ventricle and that of the right auricle-that is, between the greatest fluid

470 pressure and the least. The aortic orifice is a hole in the walls of the left ventricle, leading into the left auricle, and there is nothing very abstruse to understand in the reason why the blood flows from one cavity towards the other. Suppose a passage or sinus leading direct from the left ventricle through its substance into the right auricle: in this case, the student, the. physiologist, would smile at the idea of a long explanation of the reason why the ventricle would, at each contraction, force some of its contents into the auricle, yet it is for exactly the same reason that the circulation goes on through even the longest courses which exist for the fluids of an animal frame. The only difference between the different systems of vessels is this :-Where the communication between the right ventricle and left auricle is short, the current is a rapid one; and where the communication is more minute and longer, as in the lymphatics, the current is proportionably slower; but still the same force is at work in either casethat derived from the contraction of the left ventricle. This force applies to all vessels and cells having connexion, whether direct or indirect, with the ventricle on the one hand, and the auricle on the other,-and are there any vessels, or cells, or cavities, which have not? Are not lymphatics vessels having communication with the ventricle on the one hand, and the auricle on the other? Then why seek for some mysterious power for the feeble circulation of these vessels ? If the ventricle carries on the circulation of veins, why not also that of the lymphatics? Is there a single anatomical or physiological fact at variance with my opinion, that the circulation in the lymphatics is carried on by the left ventricle. ON THE CIRCULATION IN THE LACTEALS AND THORACIC DUCT.

Is there any

physiological fact, any experiment, which tends proposition? None that I am aware of ; and if

to invalidate this

there be any fact apparently at variance with it, I think I may safely engage to explain it. Would any one for a moment attempt to maintain that the fluid pressure inside the intestinal canal is not greater than the fluid pressure just where the thoracic duct enters the junction of the jugular and subclavian veins ? Allowing this to be the case, can any one maintain that this difference of pressure is not sufficient cause for establishing a current through the lacteals and thoracic duct? In the intestinal canal, the fluid pressure must be considerable ; at the junction of the and subclavian veins it is very trifling, and during inthere is no pressure, but a suction force assisting. The peristaltic action of the intestinal canal, or, in other the compression of the contents of the intestines by their walls, carries on the lacteal circulation. The movemuscular ments of respiration, in the following manner, assist it slightly. The abdominal muscles during expiration compress the conof the abdomen, and force the diaphragm up into the chest, and of course compress the receptaculum chili, and consequently force the chyle on into the thoracic portion of the duct. Inspiration induces the flow of chyle from the abdominal into the thoracic portion of the duct by the force commonly called suction: thus both acts of respiration aid somewhat the circulation in the thoracic duct as it passes from the abdominal cavity to that of the chest. In the upper division of the duct, during expiration, the thoracic portion is compressed, and the flow of chyle from the thoracic to the jugular portion of the duct is slightly assisted: and, last of all, emptying itself just at the point where the veins enter the chest, it comes under the assistant influence of in-

jugular

spiration

words,

tents

spiration. Why does this vessel pursue its long course through the chest, rise into the neck, and bend down to reach the junction of the jugular and subclavian? Had it been otherwise, its circulation would have been obstructed-it could not have gone

on. It system at a point near to the auricle, and where the fluid pressure is less than in any other part of the whole frame.

must enter the venous

ON ABSORPTION.

,

The power by which foreign matter, whether fluid or solid, gets into any animal frame is the same power by which soluble substances diffuse themselves through fluids in which they are immersed, or with which they are in contact. For the sake of elucidation, let us imagine an experiment or

’,

two.

The forces of the lacteal circulation are as follow :-The intestine (1) contracts upon its contents, and, by compression, forces the chyle into the lacteals. As regards the lacteal circulation, what is the intestinal canal but a heart ? A heart is a cavity with muscular walls, which at intervals compress its contents. Such is the intestinal canal. Does not the peristaltic action force fluids and solids from one end of the intestine to the other? Why not the same force carry on the circulation of the thoracic duct ? Suppose an intestine to be wounded, are not its contents forced out, during peristaltic action, through the wound or opening? Are not the mouths of the lacteals so many holes or openings out of the intestinal canal? The filaments of the organic nerves distributed to their orifices may possibly enable them to choose what fluids they will admit, or what reject; but this does not bear upon the question. Here is sufficient force. When I first dissected the thoracic duct, I drew a diagram similar to the above, to assist in the analysis of the forces of the lacteal circulation, and then at once saw that the fluid pressure in the intestinal canal must be greater than the iluid pressure in the veins at the point where the duct enters; and to me this was a satisfactory reason for the motion of the chyie, and I confess I troubled myself no further on the matter. Are these vessels constructed to bear a forcible circulation ? Are their delicate coats indicative of a stronger circulation than the muscular coat of the intestines is able to afford? On the contrary, have not these vessels about the same relation to their heart, the intestinal canal, as the aorta to its ventricle?

Experiment 1.—Take a knob of sugar and throw it into a glass of water ; it is pretty certain it will dissolve-that is, the particles of sugar, by a process named solution, will become diffused throughout the fluid. Don’t wait for this effect, but take a small wire cage, (say one used for the application of leeches,) and clap it into the water over the aforesaid nob of sugar so as to encage the sugar. Now it is a fact that the said cage would not prevent the solution of the sugar; the particles of sugar would dissolve and distribute themselves through the fluid on the outside of the cage as well as through that on the inside of the cage. Experiment 2.-Use, instead of this cage of coarse wire, one of fine wire-gauze ; still the diffusion of the particles of sugar throughout the water would go on-that is, the sugar would dissolve in the fluid outside the gauze-wire cage, as well as in that on the inside; the only difference is this, it would not dissolve so fast, its solution would be somewhat obstructed. Experiment 3.-Instead of using the gauze-wire, fold the sugar in a piece of linen, and throw it into the water, will the linen (however fine) prevent the sugar from dissolving? Certainly not, it will only retard solution. Instead of linen, use a piece of animal membrane; the effect will be the same; solution will take place, but will be still more obstructed than before, because the membrane’s pores are more minute. Why does the wire-cage slightly obstruct solution? Why the gauze-wire obstruct more? Why, still more, the linen? and why, more than either, the piece of animal membrane? Simply because solution takes place surface to surface; the more surface in contact, the faster the solution; the rapidity of solution is in the ratio of the surface exposed. The wire-cage, the cloth, the membrane, lessen the quantity of surface in contact, in proportion to the closeness of their texture, that is all ; neither cage, cloth, nor membrane, possess any power of endosmose, or exosmose, or absorption, they merely, more or less, separate surfaces which might otherwise be in contact. Animals are covered, not by wire-gauze, not by porous membrane, but by an elastic, closetextured, water-tight, horny, or scaly cuticle, which prevents injurious solution of foreign matters in the fluids of the frame. Take off this cuticle from any surface, apply a grain of morphia to the surface, the powder dissolves in the moisture on this surface, and then passes through the tissues, or rather, dissolves in

471 the adjacent fluids, the solution not being prevented by the cellular membrane and coats of the vessels, but only retarded on the principles above mentioned. It is the same with all substances absorbed into the frame of living animals; they are dissolved in the animal fluids; and this kind of absorption (solution) takes place equally in all vessels, cells, and cavities of the animal frame, according to the attraction of the fluids they may contain for the substance absorbed, (dissolved.) There is no power of absorption in any vessels of the body; there is no force of absorption existing in the human frame; there is no such phenomenon as absorption; the use of the word implies ignorance of the phenomena intended to be expressed by it; the power meant is the power of solution. This is the power, and the only power, by which foreign matter enters the system of a living animal. April, 1845.

BRITISH AND AMERICAN MEDICAL JOURNALS. CASES OF POISONING BY STRAMONIUM.

Mr. SPENCE describes, in the Boston Medical and Surgical cases of three females who had taken infusion of stramonium leaves (half an ounce to a pint of water) in mistake for horehound. He found them lying in bed, stupid, unable to articulate, with a certain peculiar wildness of countenance, and Unshed face; pupils dilated and insensible; conjunctivse highly

Journal, the

sists, at first, in the deposition of osseous matter in the form of a fine microscopic net-work; and, therefore, that the Haversian canals are only a secondary, not a primary, formation in osseous tissue. "4. That in

cases

of necrosis and

fracture, the process of

re-

of bone by the periosteum is the same."-Edinburgh production Medical and

Surgical Journal.

THE COMPOSITION OF BONE.

A very lengthened series of experiments on this subject, _ by Dr. STARK, published in the same journal, seems to afford somewhat unexpected results. That gentleman says" From these experiments we see how very nearly the same is the proportion of earthy and of animal matters in the bones over the whole animal kingdom. They seem to demonstrate that wherever a true bone occurs, that bone contains the same average amount of earthy and of animal matters. We see that there is no difference in this respect between the true bones which surround the mouth of the sturgeon, and the bones of birds or of the mammalia. Yet the sturgeon is one of those fishes so low in the scale of creation, that its skeleton consists of simple cartilage. These experiments, therefore, demonstrate the fallacy of the statement, that the bones contain a larger amount of earthy matter the higher we ascend in the scale of organization." .

INFLAMMATION OF THE SEMILUNAR VALVES OF THE PULMONARY ARTERY.

" A girl of eighteen was brought in a dying state to the great hospital of Vienna. It was ascertained that from her earliest infancy she had a very feeble constitution, was thrown into a state

of extreme weakness on the smallest exertion, which, indeed, often brought on fainting. When in that state her face became swollen and her lips livid. More lately she had been subject to palpitations, which were more especially excited on ascending a stair, and often terminated in syncope. " Several ounces of a dark but transparent serum were found in the pericardium. The heart was double its usual size, and a considerable quantity of fat covered its right margin, and the transverse auriculo-ventricular groove. The venæ cavas and the right always present. auricle were dilated and hypertrophied to an extraordinary degree. From the ’° Report of the Edinburgh Lock Hospital," we The ventricles of the heart, but especially the right one, were much hypertrophied. The tricuspid and bicuspid valves were extract the following remarks on converted on their free edge into a cartilaginous substance, DIFFICULTY OF DISTINGUISHING GONORRHŒAL FROM THE covered with numerous vegetations. The semilnnar valves of LEUCORRHŒAL DISCHARGE. the pulmonary artery bore deep traces of distinct inflammation. From our observations, we are convinced that the features were thickened, rigid, cartilaginous, and of a yellowishdescribed in works on forensic medicine, as affording a means of They grey colour."—Edinburgh Med. and Surg. Journal. diagnosis between gonorrhœa and leucorrhcea, are extremely OF THE HEART; A SINGLE AURICLE GREAT MALFORMATION fallacious. Gonorrhœa, it is said, affects the lower part of the AND VENTRICLE. while leucorrhcea from a source. proceeds higher vagina only, This may be true in certain recent cases of gonorrhœa, the result "During the first six weeks of life. the child (the subject of the of violence; but it is by no means true in the great majority of present case) seemed to thrive perfectiy well; but then the breathIn many instances which we have seen of the disease, in ing became difficult, and the surface of the face and body to cases. its acute stage, the mucous membrane of the vagina was inflamed exhibit a bluish hue. At six months, she was seized with conthroughout its whole extent, and also that of the cervix uteri; vulsions, which were followed by hemiplegia of the right side. while a discharge, exactly similar to that secreted in the vagina, This, however, gradually became less and less, and eventually the And in chronic cases, young sufferer recovered so well, that she could walk about with was also seen issuing from the os uteri. on the other hand, so far from this statement being accurate, we ease, after the right tendo Achillis (which had become conbelieve that the discharge of gonorrhoea proceeds principally tracted) was divided by M. Scoutteten. The dyspnoea and from the upper part of the vagina. cyanosis were always increased upon any exertion; the blue tint " It may be said that the characters of the discharge will was more promomce on the right side. In her sixth year the girl enable any one to distinguish between the two affections. This died of an attack of bronchitis. Dissection :—The substance of may also be true in some instances; the thin mucous discharge i the two ventricles of the heart was nearly of the same thickness of the first stage of gonorrhoea, and the purulent discharge of the’, throughout. The septum was almost entirely wanting, there stage immediately succeeding, are certainly distinctive, if taken in being no trace of it except at the lower part. The orifice of the conjunction with the other signs of inflammatory action, and are, pulmonary artery was separated from that of the aorta only by a no doubt, diagnostic. But when the affection has assumed a small spur, which formed the upper part of the circumference of chronic character, it is not distinguishable from leucorrhœa, the intr-ventricular opening. There was only one auriculoeither by reference to its seat, or the character of the discharge ; ventricular orifice, common to the two ventricles and two auricles. the discharge in both instances is the result of a similar condition These last-named cavities were separated from each other by a of the same membrane, which in some cases is pale and relaxed, thin septum, which did not reach as far as this orifice, and therein others, livid and congested. fore was incomplete. The foramen Botuiii also was so open as to " Lastiy, we have repeatedly inoculated with the matter of admit the point of the little finger. Thus it was that a free comgonorrhoea, without in a single instance obtaining a positive munication existed not only between the cavity of the ventricles result, our experiments in this respect being in accordance with and that of the auricles, but also from one auricle to the other. those of M. Ricord and others."—Northern Journal of Medicine. The auriculo-ventricular orifice was provided with a large trianvalve, that was attached to the anterior three-fourths of its gular THE FORMATION OF BONE BY THE PERIOSTEUM. and fixed at its apex to columns; carnese on the Dr. ALEXANDER WATSON has founded the following observa- circumference, of the ventricular parietes. A few columnæ, propart posterior tions on four cases of injury and diseases of bone: ceeding from both ventricles, were attached to the two lateral " 1. That the theories alleging that new bone is formed only borders of the valve. " In this case, therefore, although there were distinct vestiges of by the living parts of the old bone, in cases of necrosis and fracfour cardiac cavities, we may fairly say that the heart was simple ture, are incorrect. " 2. That the periosteum has evidently the power to produce - i.e., consisting of one ventricle and one auricle-as it exists in new bone of itself, without the aid of the old bone. Batrachian animals. The presence of a single auriculo-ventricu" 3. That the formation of new bone by the periosteum con- lar orifice can leave no doubt on this paint "—Medico-Chir. Review.

and tongue parched; no vomiting; breathing at times stertorous, and laboured; hands cold, with a trembling and slightly convulsive movement; great rigidity of the muscles of the neck and back; at times active efforts at utterance. Stimulants were administered in two cases, with apparent benefit. The third case was fatal. The writer lays stress on the absence of vomiting, a symptom said by writers on materia medica to be

injected; lips