REPRODUCTION 523 



as a certain amount of substances (biliary and other), excreted 

 by its organs during development, are found in the intestines at 

 birth. 



Human milk is undoubtedly the best food for an infant in the 

 early months of life ; and to suckle her child is useful to the mother 

 if she be a healthy woman. Many women refuse to suckle their 

 children from a belief that so doing will injure their personal ap- 

 pearance, but skilled medical opinion is to the contrary effect ; the 

 natural course of events is the best for this purpose, unless lac- 

 tation be too prolonged. Of course in many cases there are justi- 

 fiable grounds for a mother's not undertaking this part of her 

 duties; a physician is the proper person to decide. 



In a healthy woman, not suckling her child, ovulation and 

 menstruation recommence about six weeks after childbirth; a 

 nursing mother usually does not menstruate for ten or twelve 

 months; the infant should then be weaned. 



When an infant cannot be suckled by its mother or a wet-nurse 

 an important matter is to decide what is the best food to substi- 

 tute. Good cow's milk contains rather more fats than that of a 

 woman, and much more casein; the following table gives averages 

 in 1,000 parts of milk: 



Woman Cow 



Casein 28.0 54.0 



Butter 33.5 43.0 



Milk-sugar 44.5 42.5 



Inorganic matters. 4.75 7.75 



The inorganic matters of human milk yield, on analysis, in 

 100 parts calcium carbonate 6.9; calcium phosphate, 70.6; 

 sodium chlorid, 9.8; sodium sulphate, 7.4; other salts, 5.3. The 

 lime salts are of especial importance to the child, which has still 

 to build up nearly all its bony skeleton. 



When undiluted cow's milk is given to infants they rarely bear 

 it well; the too abundant casein is vomited in loose coagula. 

 The milk should therefore be diluted with half or, for very young 

 children, even two-thirds its bulk of water. This, however, brings 

 down the percentage of sugar and fat below the proper amount. 

 The sugar is commonly replaced by adding 'cane-sugar; but sugar 

 of milk is readily obtainable and is better for the purpose. If 

 used at all it should, however, be employed from the first; it 



