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through the arteries, he is going with its amazing speed to take to all the points of the economy the compensation of the losses, and the materials of the growth, and having being by those installments impoverished in one of its tropics, the capillary system of the body, begins the retrograde movement for the other, the capillary pulmonary, to assume new vitality. This way, without doubts exact, the modifications of the blood are expounded, but very succintly, when its transcendency demands larger development. There it is.

In this reciprocal action and reaction between the air and the blood, of which it results the appearence of carbonic acid and aqueous vapors, and disappearance of the oxygen, as well as change in the coloration, temperature, tension and coagulability of the blood, that increase, is observed equally that there are modified the proportions of its immediate principles. The albumin decreases, the fibrin increases and, by the absorption of the nitrogen, and expulsion of the carbonic acid and water, it improves in. absorção do azoto, e expulsão do ácido carbônico e água, aperfeiçoa-se.

This improvement is proven by the following experience. Obtained the fibrin of the veined blood, one pulverise it, and one treat it in that state with nitro and water, in given proportions, it is dissolved, and it behaves with the reagents as the albumin; the heat and alcohol coagulate it, and the mercury chlorurine, the plumbic acetate, thrown in the dissolution, there they determine precipitate.

Now, the fibrin of the arterial blood resists and it triumphs of the solvent action of the mixture of the nitro and water, nor it gives, treated by the reagents, the same results of the precedent, and this property of the arterial fibrin it comes of the influence of the oxygen. These notions were picked in Muller, that took them of Denis and of Scherer.

The increase of the fibrin is due to the transformation of the albumin, for whose operation competes, in the thinking of Burdach, the fat and I begin extractive of the kilo and lymph, that comes of wrapped up with the veined blood.

Arnol wants that a transformation of the albumin still gives place to the formation of the hematosin by its combination with the iron super-rusted during the breathing; doubtful opinion, for that that there is not certainty, as says the already mentioned Burdach, of the state of combination of the iron in the blood. The water exists in smaller amount in the fluid after arterialized in the lung, what is explained satisfactorily by the transpiration, that there is operated, and however, admirable fact and still not explained in the science, it will supply the much more abundant cutaneous perspiration and secretion of the sweat.

This fight between the air and the nutritious fluid in the lung is operated in a way it continues and not intermitently, as in fact one could infer of the intermitence between two separate inspirations by an expiration.

According to Davy, in the deepest expiration still in the lung are 35 cubic inches of air, and 108 after an ordinary expiration; and ordinarily one exhales 10 to 13 cubic inches, amount that varies, according to the largest or smaller thoracic capacity, and this way, continuing in the lung the contact of the