tion which is observed after violent muscular exertion; in typhus and other putrid fevers, in erysipelas, and the dreadful disease which originates from wounds got in the examination of a body, in which death has occurred in particular states. Further, in other cases the attraction between the globules seems entirely destroyed, or rather the blood is in such a condition that attraction is never established, the blood remaining permanently fluid, as when death has taken place suddenly, from a blow on the stomach, from hanging, lightning, violent mental emotion, cholera, and the worst forms of fevers. Some poisons, especially prussic acid and the venom of serpents, also produce the same effect. In these cases, the body hastens rapidly into decomposition, so that the more solid parts, as well as the blood, indicate the peculiar state of the body previous to death, and also the kind of the death itself.

The proportion of coagulum varies much in different animals, and in the same animal in different states, the average proportion being about one-third of clot. The extremes furnish equal parts of serum and clot, on the one hand, and one-fourth only of clot on the other: these extremes, however, are rare. Even in the same bleeding the proportions differ, the first cupful having a greater, and the last a less quantity of the more consistent part.

The serum is a pale straw-coloured greenish liquid of a specific gravity from 1025 to 1030. It contains a considerable quantity of albumen, so that on exposure to the temperature of 160° it is coagulated into a whitish somewhat translucent mass like the white of an egg. We have already, when treating of the proximate animal principles, had occasion to advert to the general properties of albumen, so that it is unnecessary to repeat what has been stated. If the coagulated serum be allowed to drain, particularly after being broken up and cut into small pieces, a watery fluid filters from it, termed

the serosity of the blood, just as we observe the curd of milk separating into the more consistent curdy part, and the more fluid portion, the whey. Besides holding in solution the different salts of the blood, the serosity contains a peculiar animal matter which is not coagulable, and when obtained in the dry state by evaporation, is again dissolved, both by water and alcohol. At one time it was considered to be gelatin, but it is not acted upon by the characteristic tests of that substance, so that at present gelatin does not rank among the constituents of the blood.

The coagulum consists of fibrin and red globules merely in a state of mechanical mixture. The fibrin is not held in solution in living blood, but appears to be formed of colourless particles, between which in the living state there exists repulsion, but on the occurrence of death attraction is established between them, so as to produce coagulation. As has just been stated, however, this attraction is variously modified, or altogether prevented by various causes. When the mass is examined by the aid of the microscope, it presents a fibrous and cellular appearance, which has been compared to the reticulated texture of the leaves of plants. When blood is stirred with a bunch of twigs, the fibrin adheres to the twigs, and may thus be obtained separate from the albumen. If too forcibly agitated, coagulation is prevented, whether we stir the blood or agitate it in a bottle. By washing the clot with water, the colouring matter is removed, when the fibrin remains nearly colourless, presenting a fibrous structure, from which it has derived its name. The characters and properties of fibrin and the red globules having been already adverted to, they need not be further noticed in this place.

The blood contains a small quantity of oleaginous matter, which may be procured separately by agitating it with ether. In some instances it is so abundant that the serum has the appearance of whey, milk, or cream, according to the proportion of fatty matter.

The following are the results of two analyses of the

Vital Properties.-Since the blood is endowed with many properties which cannot be explained either on mechanical or chemical principles, we are entitled to attribute them to its vitality. Its vitality has been disputed on the ground of its being a fluid; but even to admit (which is by no means necessary) that life is inconsistent with mere fluidity, we have seen that the blood cannot properly be termed a perfect fluid, as it contains numerous globules which are curiously organized, and displays properties different from those which result from physical agencies, and which cease on its being separated from the living organism, or on the supervention of death. Much depends upon the ideas attached to the terms life and vitality, and the keen discussions which have so often taken place originate in most cases from different accep

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tations of terms, or from the various points from which a subject may be viewed. While some have denied that the blood possesses vitality, others have gone to the opposite extreme, and considered it as the especial seat of life; and as if the writings of Moses had ever been intended for the teaching of physiology, they have appealed to such texts as the following: Genesis, ix. 4. "But the flesh, with the life thereof, which is the blood thereof, shall ye not eat." Leviticus, xvii. 11-14. "And whatsoever man there be of the house of Israel, or of the strangers that sojourn among you, that eateth any manner of blood; I will even set my face against that soul that eateth blood, and will cut him off from among his people. For the life of the flesh is in the blood; and I have given it. to you upon the altar, to make an atonement for your souls for it is the blood that maketh an atonement for the soul. Therefore I said unto the children of Israel, No soul of you shall eat blood, neither shall any stranger that sojourneth among you eat blood. And whatsoever man there be of the children of Israel, or of the strangers that sojourn among you, which hunteth and catcheth any beast or fowl that may be eaten; he shall even pour out the blood thereof, and cover it with dust. For it is the life of all flesh; the blood of it is for the life thereof: therefore I said unto the children of Israel, Ye shall eat the blood of no manner of flesh: for the life of all flesh is the blood thereof; whosoever eateth it shall be cut off." Some commentators understand these injunctions as intended to preclude such a horrid mode of using animal food as practised by the Abyssinians, who, on certain occasions, cut from the living animal flesh, and devour it, still quivering with life, and reeking in blood, at the same time taking care to avoid vital parts, that the life of the poor mangled animal may not be destroyed. Richerand thus adverts to the effects of animal diet:-9 Savages, who live by hunting, and who feed on raw, bloody, and palpitating flesh, are the most ferocious of men; and in our

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own country, in the midst of those scenes of horror which we have witnessed, and from which we have suffered, it was observed that butchers were foremost in the massacres, and in all the acts of atrocity and barbarity. I know this fact, which was uniformly noticed, has been explained by saying, that the habit of slaying animals had familiarised them to shed human blood. But though I do not deny the existence of this moral cause, which certainly operates, I think I may add to it, as a physical cause, the daily and plentiful use of animal food, and the breathing of an air filled with emanations of the same kind, which contributes to their embonpoint, which is sometimes excessive." Animal food is not well adapted for a warm climate, such as Palestine is for the greater part of the year, in which the Hebrews were destined to be placed. These appear to be sufficient reasons why the great Lawgiver imposed such injunctions and restrictions on that people, prone as they were to adopt the customs and follow the practices of their neighbours, who were sunk in the most base and degrading superstitions, accompanied with the most abominable and demoralising rites and usages.