CONCERNING CORPULENCE. 447 



becomes a load aud a drag, impeding the respiratory movements, 

 making exercise painful, and dulling the sensibilities, it is then not 

 only a source of great discomfort, but the precursor of positive disease. 



In a perfectly healthy individual, no abnormal deposition of fat 

 can be supposed to take place, at any age or in any locality, provided 

 the natural appetites and muscular powers be regulated as they ought. 

 Whenever, therefore, we see an individual unnaturally fat or lean, we 

 may safely conclude that an error exists somewhere, and that such an 

 individual either inherits a morbid propensity, or is producing for 

 himself such a propensity. 



The conditions which appear to favor an excessive deposit of fat 

 are the following : First, an inherited tendency which predisposes to 

 corpulence, yet always requiring the influence of some exciting cause 

 to bring it into activity. No one can doubt that certain families have 

 a natural tendency to corpulence, which can be often traced through suc- 

 cessive generations. It is curious, also, to obseiwe how this tendency is 

 varied in different families, and even in different individuals of the 

 same family. Thus, in one family, we see that the children and females 

 possess a striking tendency to embonpoint, while the male adults, par- 

 ticularly in advanced age, are remarkable for their leanness. In an- 

 other family, directly the reverse may be observed, the children and 

 females are lean and squalid, while the middle-aged male adults are 

 conspicuous for their corpulence. 



Climate and locality seem also to exert considerable influence on 

 the deposition of fat. The inhabitants of low, swampy situations, in 

 temperate climates, are usually remarkable for their bulky flabbiness, 

 and propensity to corpulence ; while the inhabitants of very hot and 

 of very cold climates, as well as the inhabitants of mountainous regions, 

 have, perhaps, less tendency to obesity. There is this remarkable dif- 

 ference, however, between the dwellers in hot, and in cold climates : 

 those living in hot climates rarely become fat, without becoming other- 

 wise diseased ; while the people of cold climates seem not only to derive 

 protection against the influence of external cold by the layer of fat with 

 which their bodies may be enveloped, but the carbon of the fat, com- 

 bining with oxygen during the process of secondary assimilation, has 

 with some reason been supposed to contribute to the production of 

 animal heat. 



But, of all the agencies which influence the deposition of fat, prob- 

 ably diet and exercise are the most important. Foods have been 

 divided, according to their composition, into nitrogenous and non-nitro- 

 genous. The former, including albumen, fibrine, and casein, consist of 

 only carbon, hydrogen, oxygen, and nitrogen, with some minor ingre- 

 dients ; the latter, embracing starch, sugar, and the fats, are made up of 

 only carbon, hydrogen, and oxygen. It has been thought that the nitro- 

 genous foods are consumed chiefly in the formation of the tissues, 

 while the non-nitrogenous are devoted mainly to the function of 



