A medical handbook : comprehending such information on medical and sanitary subjects as is desirable in educated persons, with hints to clergymen and visitors of the poor / by Frederick William Headland.
- Headland, Frederick William
- Date:
- 1861
Licence: Public Domain Mark
Credit: A medical handbook : comprehending such information on medical and sanitary subjects as is desirable in educated persons, with hints to clergymen and visitors of the poor / by Frederick William Headland. Source: Wellcome Collection.
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![their chief source in the sun^ from which point they radiate to our planet, as well as into the rest of j space. But while, light is only an occasional neces- < sary of life, so that being deprived of it for a j time we do not die, heat is constantly necessary, and ] a fundamental condition of the act of existence. When deprived of the rays of the sun, we have other causes at work which supply us with heat. For with- out heat, if only for a single moment, an animal would die. A temperature of from 98 to 100 | degrees of the thermometer of Fahrenheit is neces- j sary to human life, and to that of most warm-blooded animals. This temperature of the body must con- tinue the same, whatever may be the heat of the atmosphere around it. The law of heat is such that by conduction from one to another all substances have a strong tendency to become equal in tempera- ture with those which surround them. Thus a dead body becomes soon of the same temperature as the j external air. It is otherwise with living animals. The body of a man, while he lives, must continue at j the temperature of 98®, whatever the heat of the air. ] Now as the heat of the air is generally below this point, in what manner is this heat of the body kept up ? The answer is simple. Combustion, or burn- ing, is a process which consists in the combination ^ of organic substances with oxygen. This process « produces heat. In the burning of a coal or wood fire, of gas, of tallow or wax, it takes place rapidly.](https://iiif.wellcomecollection.org/image/b28140047_0032.jp2/full/800%2C/0/default.jpg)
