The Philosophy of Health; Volume 1 (of 2) / or, an exposition of the physical and mental constitution of man

by Southwood Smith

5. Again, albumen consists of azote 15-705/1000, oxygen 23-872/1000, hydrogen 7-540/1000, carbon 52-888/1000, parts. The elementary bodies uniting in these different proportions, there results a second proximate principle, an adhesive fluid, transparent, destitute of smell and taste, miscible in water, but when subjected to a temperature of about 165°, converted into a solid substance no longer capable of being dissolved in water. This conversion of albumen from a fluid, which is its natural state, into a solid, by the application of heat, is called coagulation. It is a process familiar to every one. The white of egg is nearly pure albumen, naturally a glary and adhesive fluid: by boiling, it is coagulated into a white and firm solid.

6. In like manner, fibrin consists of azote 19-934/1000, oxygen 19-685/1000, hydrogen 7-021/1000, carbon 53-360/1000 parts, forming a solid substance of a pale whitish colour and firm consistence, the peculiar character of which is its disposition to arrange itself into minute threads or fibres.

7. On the other hand, fat or oil, which is a fluid substance of a whitish yellow colour, inodorous, nearly insipid, unctuous, insoluble in water and burning with rapidity, consists of a larger proportion of hydrogen, a small proportion of oxygen, and a still smaller proportion of carbon, without any admixture of azote.

8. From this account of the composition of the proximate principles, which it is not necessary to extend further, it is manifest that all of them consist of the same ultimate elements, and that they derive their different properties from the different proportions in which their elements are combined.

9. The ultimate elements that compose the body are never found in a separate or gaseous state, but always in combination in the form of one or other of the proximate principles.

10. In like manner, the proximate principles never exist in a distinct and pure state, but each is combined with one or more of the others. No part consists wholly of pure albumen, gelatin, or mucus, but albumen is mixed with gelatin, or both with mucus.

11. Simple or combined, every proximate principle assumes the form either of a fluid or of a solid, and hence the most general and obvious division of the body is into fluids and solids. But the terms fluid and solid are relative, not positive; they merely express the fact that some of the substances in the body are soft and liquid compared with others which are fixed and hard; for there is no fluid, however thin, which does not hold in solution some solid matter, and no solid, however dense, which does not contain some fluid.

12. Fluids and solids are essentially the same in nature; they differ merely in their mode of aggregation; hence the easy and rapid transition from the one to the other which incessantly takes place in the living body, in which no fluid long remains a fluid, and no solid a solid, but the fluid is constantly passing into the solid and the solid into the fluid.

13. The relative proportion of the fluids in the human body is always much greater than that of the solids; hence its soft consistence and rounded form. The excess, according to the lowest estimate, is as 6 to 1, and according to the highest, as 10 to 1. But the proportion is never constant; it varies according to age and to the state of the health. The younger the age, the greater the preponderance of the fluids. The human embryo, when first perceptible, is almost wholly fluid: solid substances are gradually but slowly superadded, and even after birth the preponderance is strictly according to age; for in the infant, the fluids abound more than in the child; in the child, more than in the youth; in the youth, more than in the adolescent; in the adolescent, more than in the adult; and in the adult, more than in the aged. Thus, among the changes that take place in the physical constitution of the body in the progress of life, one of the most remarkable is the successive increase in the proportion of its solid matter: hence the softness and roundness of the body in youth; its hard, unequal, and angular surface in advanced life; its progressively increasing fixedness and immobility in old age, and ultimate inevitable death.

14. The fluids are not only more abundant than the solids, but they are also more important, as they afford the immediate material of the organization of the body; the media by which both its composition and its decomposition are effected. They bear nourishment to every part, and by them are carried out of the system its noxious and useless matter. In the brain they lay down the soft and delicate cerebral substance; in the bone, the hard and compact osseous matter; and the worn-out particles of both are removed by their instrumentality. Every part of the body is a laboratory in which complicated and transforming changes go on every instant; the fluids are the materials on which these changes are wrought; chemistry is the agent by which they are effected, and life is the governing power under whose control they take place.