Animal Heat
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ANIMAL HEAT.
The last number of Blackwood's Magazine1 contained a very interesting paper on Animal Heat, in which several items of information are given which our readers may not in general be familiar with. It appears that notwith standing the frequent and excessive changes in the temperature around us, and the consequent sensations of extreme heat and cold to which we are liable, the animal heat of the system in reality varies very little. What we feel and what we are, in regard to temperature, are very different things. During the shivering fit which precedes an attack of intermittent fever the actual heat of the skin is often as great as during the subsequent sensation of burning heat.
The writer in Blackwood denounces the practice of subjecting infants and children to cold and exposure, which many people think are good for them. He says:
Maternal instinct has in all ages and in all climates taught women to keep their infants warm. Philosophers have at various times tried, by logic and rhetoric, to thwart this instinct. Philosophy has been eloquent on the virtue of making infants "hardy," and has declared that cold baths and slight clothing must be as "strengthening" to the infant as to the adult. Listen to none of theee philosophers, ye mothers! Maternal instinct must not be perverted by such unphysiological teaching as that of "hardening" infants. It is true that strong infants can endure this process, but it is certain that in all cases it is more or less injurious; for the universal law is that the younger the animal the feebler its power of resisting cold, in spite of its possessing a higher temperature than the adult.
The writer objects to the commonly received theories as to the causes of animal heat. He objects to calling food "fuel," and says it is not the food, but the tissue, which contributes to form the fuel of the system. He also denies that the heat of the system is created by the respiratory process—as the animal heat of woman is somewhat higher than that of man, notwithstanding the differences in their respiration. The writer comes to the conclusion that we are in utter ignorance as to the origin of carbonic acid in the organism; it is still undecided whether it arises by a process of direct oxidation. Women respire 40 per cent less than men, yet have as high a temperature. Dead bodies, after respiration has ceased, continue often for hours with no diminution of heat. A mouse eats eight times as much as a man, in proportion to its size, and its respiration is 18 times as energetic; yet its power of resistance to cold is less. These and similar facts the writer quotes to prove the fallacy of Liebig's theory of the connection between food, respiration, and animal heat.
Notes:
1. Blackwood's Magazine, or Blackwood's Edinburgh Magazine, was a monthly magazine created by William Blackwood in 1817. Though it was published in Scotland it quickly attracted a wide readership in Great Britain and the U.S., especially for its fiction offerings. For more information, see David Finkelstein, The House of Blackwood: Author-Publisher Relations in the Victorian Age? (University Park, PA: Pennsylvania State University Press, 2002). [back]