Children in health and disease : a study of child-life.

  • Forsyth, David.
Date:
1909
Catalogue details

Licence: In copyright

Credit: Children in health and disease : a study of child-life. Source: Wellcome Collection.

Provider: This material has been provided by UCL Library Services. The original may be consulted at UCL (University College London)

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    defective, equilibration is difficult, and the child suffers from congenital ataxy. 2. The Physiology of Certain Special Functions. At the outset we must note that the chemical composition of an infant is unlike that of an adult, though the differences are quantitative rather than qualitative. By analysing the frozen and pulverised bodies of still-born infants, it has been shown that they contain less protein and much less inorganic salts, but more fat and more water, than are found in the bodies of adults. The smaller proportions of protein and of inorganic salts are sufficiently accounted for by the slight development of the muscular system, and by the cartilaginous condition of the bones at birth. The fat, which steadily increases in amount throughout foetal life, constitutes 9 per cent, of the new- born infant, as compared with 2*5 per cent, of the adult. The proportion of water, after falling throughout foetal life, stands at birth at 74 per cent, as compared with 61 per cent, in the adult.i Digestion.—The principal requirement of the young infant during his waking intervals is food. His powers of ingestion, of digestion, and of excretion must therefore be active from the first. He obtains his food by sucking—an act which is performed in two stages. First, the lips are hermetically applied to the sides of the nipple so that the openings of the milk-ducts lie within the mouth. Then the infant, by lowering his jaw, depresses his tongue and the floor of the mouth. A diminished atmospheric pressure is produced in the enlarged cavity, and by its help milk is drawn from the secreting tubules of the breast into the dilated ampullae in the interior of the nipple. The second stage of the process is reached when the infant closes his jaws to compress the nipple between his gums. The milk then flows from the ampullae into his mouth. The whole act is repeated rapidly, and when the mouth has become sufficiently filled the milk is disposed of by swallowing. The muscular energy required to suck is expended chiefly ni 1 Vierordt's Daten und Tabcllen, 1906, Jena.