0N THE BLOOD, AND ACTION OF THE BLOOD VESSELS.

0N THE BLOOD, AND ACTION OF THE BLOOD VESSELS.

591 0N THE BLOOD, AND ACTION OF THE BLOOD VESSELS. By Mr. R. VINES, Demonstrator at the Vete- rinary College. AT the conclusion of my last commun...

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591

0N THE BLOOD, AND ACTION OF THE BLOOD VESSELS.

By Mr. R. VINES,

Demonstrator at the Vete-

rinary College.

AT the conclusion of my last communica-

tion," On the Appearance of the Blood of Animals under D!tlèrent States of Excite-

ment,""Istated, that the lacteal and lvmphatic fluid of the horse put on different-appearances,

varying

under the circumstances

in which the animal

was placed, and that in healthy subjects, if destroyed when in perfect health, and moderately excited, it appeared of a white or straw colour in those parts of the lymphatic system

strong and

which are situated near the circumference and centre of the circulation ; but, on the contrary, that in many of those which are destroyed, both when under great, as well as diminished, excitement, it commonly appeared of the same character as dark venous blood in those parts of the lymphatic system which are situated nearest the centre of the circulation, as the thoracic duct, and second order of lacteals and lymphatics, and that this became evident from the function of digestion being suspended, in consequence of severe pain produced from punctures in the feet, open joints, &c. ; and also from exposure to’a low degree of temperature without food. I likewise stated, in a former communication, that from these causes the lymphatic glands contained red blood, and that on injecting the arterial system of the lymphatic glands, the injection entered the venous system, and also the second order of lacteals which arose from the glands, thereby clearly provmg, that the arterial system of the lymphatic glands, like the artelÍal system in other parts of the body, terminate m two orders of vessels, the first of which are veins conveying red blood ; and, secondly, in veins which only convey white blood, and which are usually termed the lacteals and lymphatic vessels. The lymphatic glands may, therefore, be considered as formrng a centre point between those parts of the lymphatic system, situated near the circumference and centre of the circulation, and their uses are to give origin aud termination to two orders of lacteal and lymphatic vessels, those situated nearest the circumference of the circulation being the first order, and those nearest the centre the secotid. On further investigating this subject, I have been enabled to prove, that the lacteal and lymphatic vessels (as they are usually are the minute or finer parts of the ,

termed) *

THE LANCET, No. 272, p. 4C1.! t THE LAKCET, No. 157, p. 724.

venous system, corresponding to the minute and extreme part of the arterial system, and iu which only white blood generally circulates ; and that when the functions of digestion and respiration are duly performed, these vessels absorb the chyle, or new white blood, from the surface of the intestines, and also return the white or colourless blood, from the minute and extreme parts of the arterial system, and that they likewise absoib the fluid deposited in serous and synovi:d cavities ; but when the functions of digestion become suspended, these vessels then cease to absorb chyle, and proceed to remove the fat, &c., in the various parts of the body, and then, under these circumstances, the second order of lacteals, by receiving an increased power from the arterial system of the lymphatic glands and surrounding parts, assume the same character as the veins in

general.

j

The arterial system, therefore, in all cases, controls the action of the venous, or lymphatic, and not the lymphatic the action of the arterial, as it has been generally sup. posed, for when the action of the whole arterial system becomes increased on any separate part, the action of the venous, or lymphatic system, becomes increased also. And, again, when the action of the arterial system becomes diminished, in any separate part, the action of the lymphatic system becomes diminished hkewise. I therefore consider the vessels by which the body is supported to be only of two orders, viz., arteries and veins, the arteries performing the function of numerous depositions, and the veins that of numerous absorptions ; thus the lacteals absorb chyle, or new white blood, from the intestines, which, in circulating through the lungs, and by combining with atmospheric air, through the medium of the pulmonary veins, becomes converted into red blood ; and the veins which convey red blood, as well as those conveying the white, (which are also termed the lacteals and lymphatic vessels,) when the function of digestion is suspended, absorb different parts of the body ; this is evidently the case, as the lacteals and lymphatics, under these causes of increased absorption, are found to assume the same character as the veins. As regards the blood, I am now induced to consider it to be a peculiar vital fluid, and varying its colour in animals, likewise in different parts of the body of the same animal ;-, that the red colour is not produced from colouring matter infused in the form of globules, as is commouly supposed, but that. it is a certain effect produced oil the whole mass of blood, while circulating through the lungs, in consequence of its combining largely with atmospheric air, and which, in combination with the chyle, is the true

592 when1 Life, then, or this power of the body, has dif-been termed, by Dr. John Brown, eacitade-bility, and by others, irritability, or vital grees of vitality ; in the strong parts it ap-principle ; this vital principle of the body pears red, from possf>ssing a high degree of’t’ may be considered to be imparted to it by vital power, but in the weak, or finer parts,, the blood, which derives its excitability, or it is white, from possessing less vitality.vital principle, by combining largely with When the red blood enters the minute ves-atmospheric air, water, and either animal or sels, which commonly only convey white,vegetable matter, the former through the or colourless blood, as ]S found to be the case! function of respiration, and the latter those under various circumstances of increasedof digestion ; from this it appears, that the excitement, either in the whole or any se- living- body is continually deriving its excipurate part of the body ; that then it is nottability, or vital principle, from objects in consequence of the coats of the vessels which surround it, and these, by entering becoming dilated from debility, so as to into combination with the fluids of living allow the red globules to pass, but from the animal or vegetable bodies, thereby become red blood being of a higher stimulating qua- living matter in a fluid form, termed sap, or lity than the white, and, consequently, pro- blood ; animal life consequently becomes ducing a more powerful effect on the ves- vegetable life, and this, again, in return, sels, and this is to be seen in those cases becomes animal; first in the state of a fluid, where the lacteals and lymphatics (as they but which afterwards assumes solid forms. are usually termed) become considerably in- The excitability, or power, which the living creased in size, and assume the same cha- body possesses of receiving impressions, racter as the veins. The blood, its vessels, varies in different animals, as well as sepa. and the body, therefore, act and re-act on rate parts of the body of the same animal; each other by means of the excitants which it likewise varies according to the season of support life, and when these are dulyap- the year, for in the spring and summer the plied, the vital power of the blood, its ves- excitement is quicker and stronger, while sels, and the body, become increased ; but in the autumn and winter it is slower and if gradually withdrawn, or carried to too weaker, and this is constantly seen in the great an excess, then the vital power of the inflammatory diseases of the horse, which blood, its vessels, and the body, will gra- vary in degree according to the season. dually become diminished ; organic disease, The excitement also varies at different or debility, may therefore take place, either periods of life ; in the earlystabes it is quick from the causes which support the functions and weak, and the blood will be found to being gradually withdrawn, or carried to coagulate feeblv, in consequence of contain. too great an excess ; the former mav be ing only a small portion of animal matter; termed debility from diminished excite- but in more advanced, and in the middle, ment, commonly met with in the autumnstages, and as the animal increases in and winter, in animals exposed to wet and strength, the excitement becomes more cold, and allowed only a small quantity of powerful, and the blood will then coagulate food; and the latter debility from too greatquicker and firmer, from coutaining a much excitement, frequent in spring and summer, Ilarger portion ; but in the further advanced in animals, when exposed to a higher degree periods, and in old age, the excitement will ] of temperature, and made to undergo vio- Ibe slower and weaker, and the coagulation lent, or long-continued, exertion. Then,(of the blood will be in a corresponding i under these circumstances, as I have pre- state. viously stated, (see THE LANCET, No. 272, Royal Veterinary College, p. 401,) the colour and coagulating proDec. 17, 1828. perty of both the venous and arterial blood will gradually diminish, and this will be found to be the case by examining the state of it both at the circumference and near the ROYAL UNIVERSAL INFIRMARY FOR centre of the circulation, and it also graCHILDREN. dually diminishes in quantity as well as in quality. ON Friday the 30th ult. the election ofa The blood, its vessels, and the body also, Surgeon to the Royal Universal Infirmary possess different degrees of excitement, for Children, Waterloo-Road, took place at varying according to the circumstances the Institution, when Edward Dotibletlay, inder which the animal is placed, as the Esq., Blackfriars’-Road, was elected into state of moderate, great, and dimiraished excite- the office; by a majority of 184. ment, the power which the hving body State of the poll at the conclusion of the possesses of receiving impressions from the day. objects by which it is surrounded, is For Mr. I)oubleday 362 tuonly termedi ts life. Mr. Xeiit ...... 1 .1 173 source

of the arterial

blood, and this,

circulating through the body, assumes ferent colours, varyingaccording to its

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com-

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