Hand-book of physiology / by W. Morrant Baker and Vincent Dormer Harris.

  • William Morrant Baker
Date:
1888
Catalogue details

Licence: Public Domain Mark

Credit: Hand-book of physiology / by W. Morrant Baker and Vincent Dormer Harris. Source: Wellcome Collection.

    872/910 (page 846)
    Water, the most abundant of the proximate principles, forms a large proportion,—more than two-thirds of the weight of the whole body. Its relative amount in some of the principal solids and fluids of the body is shown in the following table (quoted by Dalton, from Eobin and Yerdeil's table, compiled from various authors) :—• Quantity of Water in iooo Parts. Teeth . 100 Bile . . . 880 Bones . . . 130 Milk . . . . 887 Cartilage . • 550 Pancreatic juice . 900 Muscles . . 750 Urine. . • 936 Ligament . 768 Lyra})li . 960 . . 789 Grastric juice • • 975 Blood • . • 795 Perspiration . 986 Synovia . . ^05 Saliva.... • . 995 Uses of the Water of the Body.—The importance of water as a constituent of the animal body may be assumed from the ]3receding table, and is shown in a still more striking manner by its withdrawal. If any tissue, as muscle, cartilage, or tendon, be subjected to heat sufficient to drive off the greater part of its water, all its characteristic physical properties are destroyed; and what was previously soft, elastic, and flexible, becomes hard and brittle, and horny, so as to be scarcely recognisable. In all the fluids of the body—blood, lymph, &c.,—water acts the part of a general solvent, and by its means alone circulation of nutrient matter is possible. It is the medium also in which all fluid and solid aliments are dissolved before absorption, as well as the means by which all, except gaseous, excretory products are removed. All the various processes of secretion, transudation, and nutrition, depend of necessity ■on its presence for their performance. Source.—The greater part, by far, of the water present in the body is taken into it as such from without, in the food and drink. A small amount, however, is the result of the chemical nnion of hydrogen with oxygen in the blood and tissues. The total amount taken into the body every day is about 4^ lbs. ; while an uncertain quantity (perhaps ^ to |- lb.) is formed by chemical action within it.— (Dalton.) Loss.—The loss of water from the body is intimately connected with excretion from the lungs, skin, and kidneys, and, to a less extent, from the alimentary canal. The loss from these various organs may be thus apportioned (quoted by Dalton from various observers). From the Alimentary canal (fasces) . . . .4 per cent. Lungs . . . . . -. . . 20 Skin (perspiration) . . . . • 30 jj Kidneys (urine) . . . . . . . . 46 100