108 OF FOOD, AND THE DIGESTIVE PROCESS. 



a preparation known as Liebig's Extract of Meat has been largely intro- 

 duced, and with beneficial results, into the military commissariat and into 

 the dietary of the sick. It is made at Fray Bentos from the flesh of four- 

 year old cattle, of the Spanish long-horned breed, greatly improved by 

 crossing with English breeds, rearechon the grassy plains or pampas of Uru- 

 guay. A full-grown ox yields from 8 to 10 Ibs. of extract of standard com- 

 position that is to say, every 34 Ibs. of pure muscle corresponding to 45 

 Ibs. of meat as obtained from the butcher (including fat, tendons, ligaments, 

 cellular or connective tissue, and horns), yields on an average 1 Ib. of ex- 

 tract. The extract contains no gelatin and no fat. One pound is sufficient 

 to produce 70 pints of good beef tea, of which each pint contains the soluble 

 ingredients of $ Ib. of beef. 1 Such extract can communicate a strong flavor 

 of meat to vegetable soups, and contains the more important salts of flesh ; 

 but it must not be supposed that it can supply the place of a corresponding 

 quantity of meat to that from which it is prepared, since it contains but a 

 small proportion of albuminous compounds. 2 



66. When the results of Experience, then, are combined with the teach- 

 ings of Science, they seem to justify the following conclusions : 



i. That a due adjustment of the Albuminous, Oleaginous, Saccharine, 

 and Saline constituents of the food to the varying conditions under which 

 Man exists is of the first importance; whilst the question of the derivation 

 of the first two of these constituents from the Animal or from the Vegetable 

 kingdom, is one of secondary character ; each being capable of yielding 

 them in adequate amount, and the only condition being that the articles of 

 food shall be so selected as to supply the needful quantity. At the same 

 time it will obviously be requisite that differences should be made in the 

 diet, in accordance with climatic and seasonal variations. For when the 

 external temperature is low, an ample supply of oleaginous matter is indi- 

 cated, and may be advantageously taken in the form of butter, cocoa, fat 

 meat, or maize-bread. On the other hand, during the heat of summer, the 

 more nearly the diet is assimilated to that of the natives of tropical cli- 

 mates, in the substitution of fruits and farinacea for oleaginous articles, the 

 less will be the liability to disordered health in the autumn. :! 



ii. Experience teaches, however, that it is not a matter of entire indiffer- 

 ence, whether the Albuminous constituent be drawn from the Animal or 

 from the Vegetable kingdom ; for the use of a highly-animalized diet has a 

 tendency to raise, and that of a vegetable diet to loiver, the proportion of 

 red corpuscles in the Blood ; whilst, by a due adjustment of the proportion 

 of the two classes of components, the evil effects of the exclusive use of 

 either may be prevented. 



in. So, again, Experience teaches what could scarcely have been antici- 

 pated theoretically: namely, that notwithstanding the power which the liv- 



1 See. a pamphlet by J. L. W. Thudichum, On the Origin, Nature, and Uses of 

 Liebig's Extract of Moat, 1869. 



- See KJward Smith on Foods, in King's International Scientific Series, 1873. 



3 There can be no doubt that a large proportion of the diseases of the digestive 

 apparatus, which are so fatal among European residents in India and other tropical 

 climates, result from the habitual ingrsti-m of a much larger quantity of food, and 

 this especially of a rich and stimulating character, than the system requires. Tho 

 loss of appetite consequent upon the diminution of the demand for eombustivc ma- 

 terial, is set down to the deleterious influence of the climate ; and an attempt is made 

 tn neutralize this by artificial provocatives. So, it seems probable that many of the 

 " bilious attacks," which, in this country, are so frequent in early autumn, and which 

 are commonly set down to the account of fruit (although the subjects of them have 

 often abstained entirely from that article), are re-illy the result of the presence of an 

 excos of hydrocarbonnceoilS matter in the system, consequent upon overfeeding 

 during the summer, and must be looked upon as the natural means by which it is 

 got rid of. 



