460 On the Law of the Nutrition of Animals. 



with certainty that in the infant the relation, as in milk, must 

 be 1 to 21. 



A company of soldiers were fed on flesh, bread, vegetables, 

 legumes, beer, brandy, fat, &c. ; and from the experiments 

 made on these by Liebig, the relation of the blood-forming 

 to the calorifiant matter in the food may be accurately deter- 

 mined. By ascertaining the amount of food taken and the 

 excrement tiirown out, the quantity of food assimilated may be 

 determined, as also the above-mentioned relation. In this 

 manner the following results were obtained : — 



Belation of the 

 blood-forming to 

 the calorifiant 

 Solid matter with 

 Water, matter. solids. 

 Pounds of food consumed 4001 1655 234'6 298:1357 

 Pounds of excrement . . 294- 220i 73^ 13: 51 



Relation of the blood-forming to the ca-"\„Q- lonr— i a •? 

 lorifiant matter in the food assimilated/ ''^^•^''"^~ '' 

 As this number 4*7 is calculated from experiments made 

 on persons who undergo considerable bodily exercise, it will 

 increase* in those whose employment is sedentary. Although 

 these numbers are not absolutely correct, some important 

 conclusions may be drawn from them. 



It is evident that the relation 1 to 4-7 is almost exactly that 

 which exists naturally in the various kinds of grain. Those 

 barbarous nations which live entirely on flesh, receive a large 

 excess of blood-forming matter, which may be counterbalanced 

 either by the addition of calorifiant matter, or by increased 

 bodily exercise. On the contrary, the poorer classes amongst 

 us are obliged to live on the cheapest food they can obtain, such 

 as potatoes, &c.t, which are one half poorer in blood-form- 

 ing or nutritive matter than the different kinds of grain. In 

 the first case nature has only to get rid of an excess ; but in 

 the latter she has to supply a deficiency, which must be done 

 by bread, milk, &c. It must be evident to every one that this 

 way of living is unnatural in the extreme. A person living 



• The word in the original is " vermindern ;" but in the present case it 

 is obvious that the author means the reverse of diminution. 



f "The previous views," says Dr. Thomson (on Food, p. 173), "suffi- 

 cientl}' explain the experiments which have been made upon cows, in wln'cli 

 the result was unfavourable when they were fed on potatoes and beetroot 

 in considerable quantities, as both of these substances contain an excess of 

 calorifiant matter. It is well-known to feeders of cattle, that an animal 

 fed on large quantities of potatoes is liable to such complaints as affections 

 of the skirt and also to loss of weight. These consequently, it may be 

 readily inferred, arise from the want of the proper balance between the 

 elements of the food." — Tb. 



