OF LACTATION. 1027 



larger amount of casein, which forms a peculiarly dense curd ; and the milk of 

 the goat is tainted with the peculiar odor of the animal, which is more intense 

 if the individual be dark colored. The milk of the Ass, though differing in the 

 proportion of its ingredients, seems to bear a closer approximation in properties 

 ( 1024). The milk of the Cow will usually answer very well for the food of 

 the infant ; care being taken to dilute it properly, according to the age of the 

 child, and to add a little sugar. Where there is an apprehension of an early 

 failure in the supply of Milk, the Author has found it advantageous to com- 

 mence feeding the infant once a day with this mixture, soon after the first month ; 

 and the number of its meals may be progressively increased, until it becomes 

 entirely independent of its parent, without any abrupt transition. 



1029. From what has been stated of the close correspondence between the 

 elements of the Blood and those of the Milk, it is evident that we can scarcely 

 expect to trace the existence of the latter, as such, in the circulating fluid. To 

 what degree the change in which their elaboration consists is accomplished in 

 the Mammary gland, or during the course of the circulation, there is no certain 

 means of ascertaining. It is evident that this secretion cannot serve as the 

 channel for the deportation of any element the accumulation of which would be 

 injurious to the system ; since it does not occur in the male at all, and is pre- 

 sent in the female at particular times only. Yet there is reason to belieye that 

 if, whilst the process is going on, it be suddenly checked, the retention of the 

 material in the blood, or the reabsorption of the secreted fluid, is attended with 

 injurious consequences. Thus if, when the milk is first secreted, the child be 

 not put to the breast, an accumulation takes place, which, if not relieved, occa- 

 sions great general disturbance of the system. The narrowness of the orifices of 

 the milk-tubes obstructs the spontaneous exit of the fluid, especially in primi- 

 paras; the reservoirs and ducts become loaded; further secretion is prevented; 

 and a state of congestion of the vessels of the gland, tending to inflammation, is 

 induced. The accompanying fever is partly due, no doubt, to the local disturb- 

 ance ; but in part, also, there seems reason to believe, to the reabsorption of 

 the milk into the blood ; this cannot but be injurious, since, although but 

 little altered, the constitution of milk is essentially different, especially in 

 regard to the quantity of crystallizable matter (sugar) which it contains. The 

 instances of the vicarious secretion of milk are not numerous ; and in no instance 

 is there an^proof that the elements of the fluid were pre-existent in the blood. 

 Some of the most curious are those in which it has been poured out from a gland 

 in the groin ; but it is probable that this was in consequence of the existence 

 of a real repetition, in that place, of the true mammary structure ; this being 

 the situation of the mammae of many of the inferior animals, of which the 

 hoinologues in Man are usually undeveloped. 1 



1 The following is a more unequivocal case of vicarious secretion ; and it is peculiarly 

 interesting as exhibiting the injmious effects of the reabsorption of the secretion, and the 

 relief which the system experienced when it was separated from the blood by the new 

 channel. " A lady of delicate constitution (with a predisposition to pneumonia) was pre- 

 vented from suckling her child, as she desired, by the following circumstance : Soon after 

 her delivery she had a severe fever, during which her breasts became very large, and 

 hard ; the nipples were swollen and firm ; and there was evidently an abundant secretion 

 of milk ; but neither the sucking of the infant, nor any artificial means, could draw a sin- 

 gle drop of fluid from the swollen glands. It was clear that the milk-tubes were closed ; 

 and as the breasts continued to grow larger and more painful, purgatives and other means 

 were employed to check the secretion of milk. After three days the fever somewhat 

 diminished, and was replaced by a constant cough, which was at first dry,' but soon after 

 was followed by the expectoration of simple mucus. After this, the cough diminished 

 in severity, and the expectoration became easy; but the sputa were no longer mucous, 

 but were composed of a liquid, which had all the physical characters of genuine 

 milk. This continued for fifteen days ; the quantity of milk expectorated amounting to 



