ECLECTIC. MONTHLY MAGAZINE OF USEFUL "Our needful knowledge, like our needful food, CINCINNATI, JANUARY, 1871. to the ends they were to serve, we must admit that originally and inherently we have the conditions necessary to good health. Good health comes from a proper use of our bodies, disease comes from abuse. He who uses, and uses it rightly, has the promise of health; he who fails to use it, or abuses it will certainly suffer disease. The law of our being is, that every function of our bodies should be brought into use. That normal use gives health to the structures, and increased power of life and reproduction. If we take the stomach as an example, we Briefly, it is that condition in which all the find that temperance in eating and drinking, functions of life are well performed. Some of gives good digestion, and the sensations are all these functions, and the more important of pleasant. On the contrary, intemperance in them, are performed unconsciously to us. eating and drinking, by overworking the organ, Those of which we are conscious, always give gives that condition of disease we know as pleasure if healthy. dyspepsia. We may say then, that health is the state of normal activity of function, and our consciousness of these activities is always pleasurable. If one is thus in the full enjoyment of health, every act of life gives pleasure. Pleasure attends eating and drinking, the digestion of food, respiration, excretion, the exercise of the muscular system, and the brain. How may we know that health is lost? We recognize the loss of health, in our own bodies, by unpleasant sensations, when normally we should have pleasant ones, or where we have never felt any before. Thus in the case of the stomach, liver, or bowels, we have the unpleasant sensations of weight, fullness, burning, knawing, pain, and we know that the condition of health is lost-we have disease. How is good health maintained? When we reflect that our bodies were made by that Great Architect, who conceived all things in wisdom, and accurately adapted them If at any time we have the evidence of approaching disease, the first object will be a return to the normal use of the part affected. In a large majority of cases we will find that the restorative powers of the body will then be sufficient for complete restoration. Over exertion-exhaustion-is one very common cause of disease. We overwork ourselves in the field, the shop, or anywhere, and the result of such overwork is an enfeebling of all parts. It is now that the body is incapacitated to resist causes of diseases. If we are chilled, there result internal congestion, and impairment of the blood. If we are exposed to malarial exudation, the vital power that should resist them is deficient, and intermittent and remittent fever is the result. Or if exposed to the peculiar fever-poison that reduced typhoid or typhus, the want of resisting power, is the primary cause of the severe illness. The first lesson we learn is, that in the use of our bodies we should never indulge in excess, for that impairs the life and the power to resist of the increased excitement, when the skin feels disease. The second is, that when we know we burning hot to the physician, while the patient are to be exposed to causes of disease, we should himself still feels deadly cold, and the internal never be exhausted, but have the body in vital organs only recover their temperature when healthy condition to resist and throw them off. the blood that has been heated in the extreme As it is this inherent vital power, that resists circulation arrives at the heart, from which it is causes of disease, so is it this power that sent first to the lungs, afterwards to the left throws disease off, and restores normal structure ventricle, from this to the brain, and all over and function. The third lesson, therefore, is, that to get rid of disease, we strengthen the life of the body, and its exercise in the important functions of life. ANIMAL HEAT. the body. It is then that the re-action and the heat become universal. Now, as the blood in the extreme vessels all over the system is the first to lose its temperature, in the cold stage of fever, and the first to become warm in the hot stage of the disease, we must look, not to the lungs, but to the chemical changes which the blood undergoes in the extreme texture, as the The doctrine of animal heat is far from being cause both of the generation and the immediate settled; but it is evident, that wherever the car- evolution of that heat which enables all warmbonic acid is formed, there the heat must also blooded animals to maintain their natural high be evolved. The generally received opinion, I temperature, even when surrounded by the coldbelieve, is, that this acid is formed in the lungs; est air. but, from many facts, I have long ago been led to the belief, that the acid is formed and the heat is evolved, not merely in the lungs, but all over the animal frame in the extreme texture, where the blood is converted from arterial to venous. I was first led to form this opinion in consequence of certain phenomena that occur in the cold stage of the marsh fever, from which it is very evident that the heat is evolved, not in the lungs, but in the extreme vessels, all over the living body. We are told by one writer, that the heat which maintains the temperature of the body, is produced by an action; and that this heat is evolved in the stomach. We are informed by another, that it is a secretion, and produced by the nerves; while others maintain that it is the effect of the vital principle; and that too, even after it has been proved that the temperature can be kept up and increased in animals, after their heads have been separated from the body. The brain and the nerves are necessary for The force of the circulation, and the quantity other purposes, but they are not essential for of heat evolved in the system, invariably keep the evolution of heat. Caloric is evolved in pace with each other. The extreme vessels, common combustion, independent of nerves; which are probably most concerned in the evolu- and by a similar process heat is often evolved in tion of heat, are more under the influence of the living animal without any assistance from the brain than the heart itself: and when this the nervous system. A limb, for example, that organ, as in fever, is supplied with impure or has been completely paralytic for many years, diseased blood, its functions are deranged, and can generate heat, long after all commuuication the nervons system suffers in common with with the brain has been completely destroyed. every other function of the animal body. In And as this is the fact, we must look, not merely the commencement of the disease, the extreme to the brain, or the nervous influence, when we vessels appear to be the first part of the vascular try to explain the cause, why the more perfect solids which feel the effects of the remote animals can maintain a high temperature, even cause; their action becomes languid, and in when surrounded with air that is a hundred deproportion as this takes place, the animal heat grees colder than the blood. ceases to be evolved, in its usual quantities, the It is certainly the easiest way of accounting temperature of the blood in the extreme vessels for difficulties by referring them to the nervous soon falls, the skin and the extremities become system, or the living principle; but this sort of cold, and when the blood, which has not been explanation generally leaves us just where we properly heated in the extreme circulation, were. The nerves, of themselves, are not the arrives at the vital organs, the whole system is cause of heat, or the cause of impressions; they then chilled into a state of complete torpor. are merely the medium by which these are conEven in mild fevers, such as the marsh inter- veyed. The nerves may convey the impression mittent, the patients sometimes die during the of heat to the brain; but these agents can not cold stage; but, in general, re-action soon of themselves evolve heat in the extreme texture comes on, and when it does, it commences first of the living body. When, for example, we tie in the extreme vessels: and there is a period, in the large artery leading to a limb, do the nerves, such cases, immediately after the commencement of themselves, though they be left uninjured, keep up its temperature? And were it not for the blood that is carried into the limb by the anastomosing branches, would it not, nerves and all, immediately become cold as death, and speedily die? The nerves have some share in the mere quantity of heat that is evolved. But even this they possess only indirectly, or inasmuch as they have some influence over the motion of the vessels in the extreme circulation; and, for this reason, in a limb that is completely paralyzed, the heat is not quite equal to what it is in another limb that is not paralytic. But still, in a limb where the nervous power is completely lost, the heat continues to be evolved through life; and, in some cases, as in the hot stage of fever, the animal heat is greatly increased. And if a limb, under such circumstances, can generate even one particle of heat, we may infer, that though the nerves may assist, yet they are not essential in the process which is incessantly going on for the evolution of that heat which is the cause of the high temperature in all those animals which have a double circulation and warm blood. These experiments, however, have since been. repeated by Dr. W. Philip, L. Gallois, &c., ; and when pains were taken by these gentlemen not to force too much cold air into the chest, it was found, that even dead animals possessed the power of evolving heat. Now, if we can keep up the temperature in a dead animal, even after the head has been separated from the body, and if a paralytic limb can not only evolve, but even increase its heat, as in the hot stage of fever, we may then safely infer that the generation of animal heat is neither a nervous action, nor a mere vital process, but produced by a chemical change which is incessantly going on, not in the lungs, but in the extreme textures all over the living body. It has been ascertained by the experiments of Dr. Prout, and confirmed by those of Edwards, &c., that the quantity of carbonic acid thrown off by the lungs varies considerably, from various causes. It is greatest about mid-day, least at midnight; greater in the prime of life than in youth or in old age. In fact, whatever increases the force of the circulation in the extreme vessels, increases, at the same time, the quantity of heat that is generated in the system, and, of course, the quantity of carbonic acid which is evolved in the lungs. It was found in Mr. Brodie's experiments that the temperature was diminished even when the respiration was kept up by artificial means. One cause of this is, the circumstance that the extreme vessels where the heat is formed are Every part of the system evidently provides more under the influence of the brain, than its own heat; and that the quantity generated either the heart or the great arteries; and when depends upon the rapidity with which the blood the head of an animal is cut off we can scarcely circulates through the extreme vessels, is very expect that the blood will circulate as freely in evident from what occurs during the process of the extreme vessels, as it does in the natural inflammation. In this disease, though the rescirculation of a living animal which possesses piration is not more frequent than in health, yet its full vitality. But, besides this, it is very when the circulation is greatly increased in any evident that, in these experiments, too large a one part of the body, the quantity of heat proportion of cold air was forced into the lungs. evolved in the affected part is infinitely greater The temperature of the air that was used ranged than it is in the rest of the system, where the from 57° to 64°; that is, from 38° to 45° lower blood is circulating at its usual rate. It is also than the natural heat of the blood of the a fact, that during the hot stage of the climate animals. Rabbits breathe from thirty to thirty- or endemic yellow fever of the West Indies, five times in a minute, but the lungs were inflated even when the general excitement is very great, much more frequently than this, and in one of the respiration is scarcely increased; but the the experiments they were inflated at the rate of quantity of heat evolved all over the body is, at from fifty to sixty. We know also that the lungs one period of the disease, so great, that it is can contain a much greater proportion of air almost painful to touch the skin. It is also than is ever used in the process of natural res- true, that in the last stage of this fever, when piration; and when the air-cells are more fre- the saline ingredients of the blood are nearly quently and more fully distended with cold air exhausted, the patients become weak, the circuin a dead animal, than ever they are in the com-lation flags, and the respiration increases exactly mon respiration of one that is alive, under such in proportion as they become cold and exhausted. circumstances we can scarcely be surprised that the blood in the lungs should become cold, and that this cold blood should diminish the heat in the whole body; particularly in a dead animal, where vitality is not present as an agent in the process, and where the usual quantity of heat can not be evolved in the extreme circulation. There is then little heat evolved in the extreme textures, there is little carbonic acid added to the venous circulation, and the blood becomes black, not from an excess of this agent, but from the decomposition or almost entire loss of its natural saline ingredients. It is well known that the temperature of a surface in a state of active inflammation is often several degrees higher than that of the arterial respires about twenty times in the course of a blood with which it is supplied. From this fact minute; but those animals that have a higher alone, it is very clear that the extra heat can not temperature breathe much faster than this. In be produced merely by the addition of a colder these, the grosser ingredients of the blood are fluid to the inflamed part; and if the blood can frequently renewed, and the solids themselves be heated, even at a great distance from the are constantly undergoing an incessant and rapid lungs, we may infer that every part of the living change, which does not appear to be required in body possesses an apparatus within itself, which cold-blooded creatures, or to be otherwise necesenables it to maintain its high temperature by the sary in those that have warm blood, except for incessant generation of its own caloric. the purpose of evolving heat. If the animal heat were generated in the lungs, The material of carbonic acid exists in the we might then, at will, increase the temperature, blood; the carbon is derived from the nutritive merely by breathing for a time as quickly as pos- fluid, which enters the circulation through the sible; a person, however, who is surrounded by medium of the thoracic duct; the oxygen is ata cold medium can not keep himself warm tracted into the circulation in the lungs; while merely by rapid respiration; but by exercise or the vital principle of the blood is, probably, motion we increase the action of the extreme derived from another and a higher source; but vessels; by increasing this, we increase the tem- its carbon, and the other grosser ingredients, are perature of the whole body; and in this way the derived from the chyle. It is by this combinablood is enabled to maintain its own high heat, tion of chyle, air, and vitality, that the blood is even when the surrounding medium is intensely formed; the arterial blood, however, from the cold. time that it leaves the lungs, suffers no change It is almost incredible how small a quantity in its properties until it arrives in the extreme of nourishment is necessary to enable the coldtextures all over the system; for as I have said, blooded creatures to support life. They breathe even in the most minute arteries, the blood is slowly,* their blood is seldom renewed, and the as highly arterial as it had been in the left side small quantity of food which is taken into the of the heart, while the blood, even in the smallest system is expended almost entirely for the nour- veins, is also completely venous consequently, ishment of the solids; and for this purpose but the change from arterial to venous, evidently very little appears to be required, as their solids, takes place only in the extreme texture; this like the blood, are but seldom changed. In change is evidently produced by the addition of some of these creatures one good meal in three carbonic acid, and we all know that whenever or months is quite sufficient, while others can live wherever this acid is formed, heat is invariably on less yet, even with this, they are active, generated; now as the carbonic acid is evidently muscular, and strong, in proportion to their size. formed in the extreme texture, it is very clear I have seen, for example, a large rattlesnake, that there also the animal heat must be evolved. which, it was said, had not tasted either food or water for nine months, yet he was plump, active, and venomous as those in the woods. When blood is exposed to destructive analysis, carbon is found to be the largest constituent; it is, also, the chief ingredient in the solid strucOn the other hand, the quantity of food which tures. We know also that the whole of the is consumed by all the warm-blooded animals, solids are formed from their nutritive fluid; is evidently much greater than is necessary for but in all those animals that have a double cirthe mere nourishment of their solid structure; culation and a high temperature, even the solids, those animals, too, which have the highest tem- like the blood itself, are incessantly undergoing perature, invariably use the largest proportion a variety of changes, particularly in the extreme of food, and when this is withheld they soon texture all over the body, where the arterial die. Ducks, fowls, &c., are (when they can get circulation ends, and the venous begins. It is food) almost constantly eating; and as all an imals that have warm blood use much more food than is actually necessary for the nourishment of the solids, or the supply of the secretions, we may infer that a great proportion of this is used as so much material for the incessant evolution of that animal heat, which is as necessary for their existence as the air which they breathe. While in health, a human being generally *I once counted the respiration of a young alligator, and though he was agitated from having been laid hold of, he breathed only from three to four times in the course of a minute. there, by a process as if for the express purpose of evolving heat, that in all warm-blooded animals, a portion of the carbon of the old solids is liberated or evolved in a free state; it is there that this fixed agent attracts to itself a part of the oxygen from the arterial blood. It is there that the animal heat is evolved, in consequence of the chemical combination of these two agents; it is there that the carbonic acid is formed and added to the venous blood, as a necessary evil; for this is the result of that process which is so essentially necessary, in the |