CHEMICAL SCIENCE. 221 



isting amount of vital power, and that which only tends to prevent 

 loss of vital power, two circumstances which, in practice, are com- 

 monly confounded, and showed that beef-tea, wines, and brandy, 

 can act only in the latter mode, while the cereals act in the first- 

 named manner. Hence, in cases of prolonged exhaustion, where 

 there has long been more waste than supply, the former is not suf- 

 ficient, and it is essential that the latter be added or substituted. 

 The action of milk is exceedingly analogous to that of the cereals, 

 both in extent and duration, and the combination of the two appears 

 to be the most perfect kind of food. The caseine is to milk what 

 gluten is to bread, and the oil in the milk,,with substances (respi- 

 ratory excitants) which call it into action, act in a manner quite 

 analogous to the common combination of bread and butter, or of a 

 mixture of fat and lean flesh. The author showed that milk and 

 flesh were the best and most natural modes of administering fat, and 

 altogether preferable to the administration of separated oils. He re- 

 ferred to the frequent use of skimmed milk in Germany as a medici- 

 nal agent, and of sour milk in Greece and America as a part of 

 food; and explained the action of the former, by its caseine and 

 sugar as respiratory excitants ; and that of the latter by the advan- 

 tage of administering lactic and other acids in that combination in 

 the summer season, and at other times, when the blood, by tending 

 to undue alkalinity, is less capable of carrying on the oxidizing pro- 

 cess. He showed that in fevers skimmed milk is preferable to new 

 milk. 



As fats lessen the respiratory changes, they ought to be com- 

 bined with other articles of food which increase their action. The 

 author referred to the importance of determining the seasons for the 

 administration of both fat and starch, and showed that there is less 

 difference in the relative amount of these two substances, used in 

 different climates, than has been commonly believed. He attached 

 importance to the physical properties of fat, and explained the bene- 

 ficial action of that substance when applied to the skin. He thought 

 this latter mode of employing fat to be especially fitted for cases of 

 debility, with lessened appetite, and perspiring, soft skin, in which 

 state the waste is always greater than the supply. The beneficial 

 action of sugar was insisted upon ; and the love of the French for 

 sugar and water was explained by the refreshing coolness, the innoc- 

 uousness, and the agreeable flavor of the fresh-made beverage, and 

 the great freedom and lightness of the respiration which attend its 

 action. He thought the ill effects of sugar in the healthy system had 

 been exaggerated. The action of animal substances in increasing 

 the respiratory process, in addition to the supply of plastic material, 

 was dwelt upon, and shown to.be of great value to the system. 

 These are allied to gluten, and some of them probably act as fer- 

 ments ; and, in illustration, he especially cited cheese, which pro- 

 motes assimilation if taken in small quantity, but is apt to disturb it 

 if much is eaten. Tea was shown to cause increased waste, and to 

 excite every function of the body, and hence was well fitted to cases 

 where there was a superfluity of material in the system, or where 

 we otherwise desire to induce a temporary increase in the vital ac- 

 tion ; but is injurious to those who are under-fed, or in any case 



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