DIET OF CHILDHOOD.] 



CHEMISTRY. 



361 



cause of its growth. It shows how the nutrition is in 

 proportion to the excretions ; a circumstance which we 

 have before shown to be the condition of growth and 

 increase of weight. 



In the infant, therefore, change of matter only follows 

 the same law observed in the adult. In both, the attrac- 

 tive power of the tissues towards the constituents of the 

 blood induces nutrition. If, from the peculiarity of their 

 composition, the tissues attract and detain a greater 

 proportion of the blood than is lost by excretion, the 

 blood, in order to maintain its composition, has to receive 

 a larger quantity of the alimentary principle than would 

 have been necessary if the activity of the nutrition had 

 been simply equal to that of the excretion. 



The direct expenditure of the blood upon the tissues, 

 therefore, determines its supply ; only the different com- 

 position confers upon the freshly-formed constituents of 

 the tissues a greater constancy ; and for this reason the 

 body appropriates more than it eliminates. 



This explains why children take proportionally more 

 food, and especially why they take it oftener than adults, 

 although the latter discharge a greater quantity of car- 

 bonic acid and urea than the former ; and thus the regu- 

 larity of the phenomena establishes the law as it can be 

 proved that the exception was only apparent. A law 

 its full validity only when the exception which with- 

 1s its authority merges in the law, as soon as the 

 itions of the seeming anomaly have been more ex- 

 'Oertained. 



sophically, we come to the conclusion that the 

 sup; :v is regulated by the expenditure, and that in the 

 infant, as in the adult, the exchange of the constituents 

 of the blood is rightly denominated the change of matter. 

 Practically, it results that the child's frequently recurring 

 lesire for food does not arise from mere ennui or rest- 

 lessness, but from processes going on in the interior of 

 the body. Hence the rule that the infant should not be 

 trained by the power of habit to a diminished and less 

 frequently manifested desire for food, but that its in- 

 stinct ought to be satisfied ; for such is the general and 

 natural expression of a law regulating the ]K'culiar change 

 of matter, which causes the inclinations of the child to 

 differ from those of the adult. 



It is, therefore, quite proper that, at first, the mother 

 should give the breast to the nursling as often as it 

 awakes. Gradually the child desires milk less frequently; 

 and in the distribution of the meals for her child, the 

 wakeful eye of the loving parent may tmst to her own 

 observation. On an average, the child, after being 

 suckled, can wait three to four hours until the next 

 meal. Very healthy and strong children freq uently sleep 

 even for six or seven hours together, without being 

 awakened by the want of food. 



The child, after weaning, does not require any food at 

 night ; and the same rule holds good for boyhood. 

 During healthy sleep, the change of matter in children 

 is moderate. This explains why even those whose want 

 of food is generally so great, can easily wait from supper , 

 to breakfast without eating anything ; while, during the 

 day, the desire of food has to be frequently satislied. 

 It is a very wholesome custom to give to children a slight 

 repast between breakfast and dinner, and another be- 

 tween dinner and supper nothing, indeed, tends better 

 to temperate habits ; for, in order to thrive, they have 

 to convey to the blood the same quantity of nutriment, 

 whether they take it at three or five times. In the latter 

 case, the stomach is less gorged at any one time; digestion 

 and the formation of blood go on witli greater ease ; and 

 in the process of nutrition there is less danger that too 

 great a quantity of nutriment should be conveyed to the 

 tissues, which might have an injurious effect, especially 

 upon the brain. 



On the other hand, children are very materially injured 

 by being gratified whenever their excitable pa'l.it.i asks 

 for food or dainties ; for, as the formation of all secre- 

 tions requires due time, just as the development of the j 

 ovum, &c., and the accumulation of milk, are bound to 

 certain periods, so the digestive fluids the saliva, for ! 

 instance, the gastric juice, the bile and pancreatic juice 



TOL. I. I 



are only secreted in a sufficient quantity for the u-Uol 

 meals. We must, therefore, allow the digestive glands 

 the needful time to prepare and collect them, between 

 one meal and another. If not, the requisite power of 

 digestive action is deficient, just at the time when the 

 most nutritious aliments, soup and meat, are taken. At 

 table, if children complain of want of appetite, and if, 

 accordingly, they do not eat, the blood becomes deficient 

 in the best alimentary principles ; if compelled to eat, 

 on the other hand, imperfect digestion makes them lan- 

 guid and thin. 



94. Milk as Food for Children. That milk is the 

 most appropriate food for children is so generally recog- 

 nised, that science has nothing to do but to confirm and 

 interpret the fact. 



Combining in a due proportion solid and liquid food, 

 milk contains not only in the caseine an albuminous 

 substance, which is transformed into albumen and tibrine, 

 afterwards into gelatine, horn, and elastic fibre ; but it 

 has also, in its peculiar sugar, one of the most easily 

 digestible constituents of fat ; and in butter there ara 

 the ready-formed fats, which assist in forming the soft 

 cushion of round limbs and full cheeks in children. 



But it is the phosphate of lime, so abundantly contained 

 in milk, which particularly constitutes this the most 

 fitting nutriment of the babe. In milk, more than in 

 any other food, the conditions are furnished for the con- 

 version of the cartilages of the infant into bones. The 

 phosphate of lime, so constantly associated with the 

 caseine, is easily dissolved by the lactic acid, into which 

 the sugar of the milk has been transformed by the 

 bile ; and thus the dissolved lime-salt passes from the 

 ' ive canal through the blood into the bones. The 

 phosphate of potash performs the same oiiieo for the 

 growing muscles. 



In the milk of animals we find the same constituents 

 as in human milk. Can, therefore, the latter be sub- 

 stituted for the former i 



A direct comparison of the milk of the woman with 

 that of the Mammalia, decides the question in the nega- 

 tive ; that of woman contains a much smaller proportion 

 of caseiue, a smaller proportion of butter and of salts, 

 but a greater quantity of sugar of milk and of water 

 than is found in the milk of cows. 



But whoever has attentively followed us in the de- 

 scription we have given of the change of matter, will not 

 see anything fortuitous in this difference of composition. 

 Here, as in many other cases, the manifold links are 

 wanting, which enable us, step by step, to prove the 

 differences of power to be nothing but differences of 

 matter : occasionally we have a better knowledge of the 

 matter than of the force, and sometimes the reverse. In 

 a thousand instances, however, the power has been so 

 distinctly proved to be a necessary quality of the matter, 

 that, like all other qualities, it is an inseparable charac- 

 teristic of the body, conditioned by the peculiar compo- 

 sition of its substance. 



It is no empty prejudice to state, nay, it is a real belief 

 in the general prevalence of a demonstrated natural law, 

 that the nature of the mother is communicated by the 

 milk to the child. And there is no thought more natural 

 than the belief, that on the breast of its mother the 

 infant may imbibe, together with the milk, her nobleness 

 of mind, with the love which devotes that food to the 

 most sacred purpose, and fastens still more strongly 

 nround the feeble child and the tender mother, the ties 

 of their endeared relationship. 



There are certain differences, though slight, between 

 the milk of one woman and that of another ; and as in 

 successive months after confinement the milk alters in 

 composition, the difference is so much the greater, as the 

 children of the mother and those of the wet-nurse differ 

 from each other in age. Since, in any case, the milk of 

 the wet-nurse will be dissimilar to that of the mother, 

 the closest possible conformity ought to be secured, 

 where a wet nurse is sought, between the ago of the two 

 children. Under any circumstances, howuver, the milk 

 of a wet-nurse more resembles that of the mother than 

 cows' milk ; and therefore the milk of a wet-nurse is to 



3 A 



