ON THE MILK OF WOMEN.

A considerable portion of the history of this species of milk, is implicitly comprised in what has just been stated; a circumstance which

justifies us in having devoted so much space to general considerations. komere is 8e24 are even very considerable within the limits of the physiological state, bariable

There is probably no kind of milk, observe Deyeux and Parmentier, the properties of which vary so much, as those of the milk of women. These variations, according to circumstances and to individuals,

so that it is a difficult matter to define their characteristics in a precise manner.

Physical qualities. The authors above cited, admit in their excellent treatise, three kinds of milk observed in nurses equally robust and in good health: 1st, that which is very serous and semi-transparent; 2nd, that which is very opaque, having the appearance of cow's milk of good quality; and 3rd, milk possessing intermediate qualities, and this was most frequently observed.

The milk is yellowish during the first days of lactation; it afterwards becomes of a more or less opaque white colour.

The odour of women's milk is mawkish, and resembles that of cow's milk.

Its taste is milder and sweeter than that of the latter.

Its specific gravity varies between 1.020 and 1.025, and may even exceed this maximum limit.

In recent researches, at present unpublished, but of which posterity will be proud, MM. Vernois and Becquerel, from eighty-nine analyses of the milk of women, have determined the extreme numbers of its

specific gravity to be 1025.16, and 1046.18, which will give a mean

of 1032.67.

Their chemical analyses, moreover, furnished the following results on the proportion of the elements of this liquid.

Under the microscope, the particular milk we are examining, like all others, presents itself under the form of a transparent liquid, in the midst of which oleaginous globules float, the characters of which are known; but which, in this instance, present a greater and more uniform size than in the other kinds of milk.

In addition, when more carefully examined, fragments of epithelium may be discovered.

Chemical properties. According to the researches of M. Donné, the milk on its escape from the breast is always alkaline; consequently,

& Alaluuit restores the blue colour of litmus paper reddened by an acid; this

action is even rather energetic. This character was for a long time misunderstood, in consequence of the mistake into which the earlier chemists fell, who, probably, only experimented upon cow's milk which was not fresh, and already a little acid. The observers who came afterwards-persuaded that the same should be the case with the milk of woman, especially as the presence of free lactic acid was generally admitted in this secretion-contented themselves with placing Alte el it in contact with blue litmus paper.

shauns

The fact is, that milk, like certain other organic liquids, possesses the singular property of changing the above-mentioned blue colour to red, without being really acid; and this has been considered sufficient to support the assertion that the milk of women possessed an acid character.

Practitioners have also, probably, been deceived by other circumstances, if, for example, they have contented themselves with the application of the test paper to the end of the nipple whilst they pressed the breast; for we know that this part of the organ, being often covered with a layer of dried milk, may possess an acid reaction. The saliva of the child which has just sucked may also be acid in certain cases.

If we lay too much stress on these data, it is with the view of warning practitioners against the error into which they may fall when about to investigate the good or bad qualities of the milk of a

nurse.

Left to itself, and at rest, the milk of woman becomes covered with a layer of cream, the thickness of which varies according as we experiment upon one or other of the three varieties of milk above described. It is proportionately thicker as the milk is more opaque, that is to say, more rich in fat globules; sometimes only a thin pellicle is formed. The cream in a thick layer, or, in other words, that formed from the milk the most charged with fatty matter, is tenacious, and alone possesses, according to Deyeux and Parmentier, the property of furnishing a mass of butter by churning. This butter is yellow, consistent, and of an insipid taste.

Meggenhofen has shown that most frequently the milk of woman al is not coagulated by hydrochloric and acetic acids. Rennet, on the contrary, always effects its coagulation, and determines the formation ital of small curds. The real clot is but very rarely observed, because the milk of women is one of the poorest in caseum. Besides, this caseum does not possess, like that of the milk of the cow, a certain

MAT
Etuet facility of being moulded and united in consistent masses; it presents

itself under the form of isolated flocculi, which cannot be made to coalesce.

Let us add, that considering the small proportion of caseum in the milk of women, and, consequently, the less specific gravity of its liquid portion, we may conclude that its cream collects more slowly on the surface than in the milk of the cow, which always serves us for comparison. Summary of the characteristics of the milk of women. The milk quickl of woman may be distinguished from other kinds by its sweeter taste, by its small proportion of caseum, which is wanting in cohesion, and forms, with acids, soluble compounds; lastly, by its cream, which most frequently does not produce any butter.

This being established, let us proceed to the study of the variations alw which this kind of milk may present in the physiological and in the abnormal or pathological state.

PHYSIOLOGICAL MODIFICATIONS OF THE MILK OF WOMEN. It is in the accomplishment of the secretory functions that we observe in the highest degree the influence of the primary forces which support life, and which give to it the stamp of individuality in each ruik living being. Thus, supposing the texture of the mammary glandul to be identical in different persons, the milk will not be always alike; it may vary every instant under the influence of the most different causes. No two specimens of the milk of women in good health are absolutely alike; and in the same person, the milk may change in composition from one instant to another.

The circumstances which influence the composition of the milk in the normal state, are—1stly, the idiosyncracies; 2ndly, the time that has elapsed since delivery; 3rdly, the interval between the last repast of the infant, or that from the commencement of the repast which is interrupted in order to make the observation; 4thly, the alimentary regimen; 5thly, the genital functions; 6thly, the constitution and the temperament.

Individual idiosyncratic modifications. The differences which the milk presents in nurses who are in the same apparent conditions of vigour and health, have been already pointed out; it is, moreover, well known, that certain women who appear weak, are, notwithstanding, excellent nurses; whilst others, who are very robust, have a scantybiln and unwholesome milk.

M. Donné mentions the case of a woman whose milk was extremely rich in butter, and presented globules of a very large size.

On the contrary, a certain number of nurses whose milk is poor, constantly present milk globules of very small dimensions.

It must be admitted that there is nothing positively decided on

this point, and I feel certain that the composition of the milk varies

Chicality according to the vitality and individuality of the mothers, under the Guik the different operations of the organism; but we are ignorant of CHING I the extent of this action on the relative quantities of the elements cwing of the milk, and also on its nutritive qualities, independently of its

influence of the nervous force which animates, directs, and co-ordinates

itality composition, which is probably different, and which constitute two

distinct questions. Nevertheless, some attempts have been made. M.M. Vernois and Becquerel have endeavoured to determine the e value of these various influences; and if definite conclusions have not resulted from their investigations on this subject, this assuredly is not the fault of these observers, but must be exclusively referred to the difficulties of the subject, which must be examined from another point of view.

The following analyses of milk of women with breasts more or less developed, and of brown and fair women, may confirm the above remarks; but in order to comprehend their signification, they must be compared with the analysis of normal milk. The means, deduced from a large number of particular analyses, are only given:

[L'Heretier (Traité de Chimie Pathologique, p. 627) selected two females of equal age, and made them submit to the same diet and mode of life. The following are the results of his analyses:

He appears to have selected the analysis that presented the most marked contrast; for he observes, that if he had taken the mean of all his analyses, the difference between the amount of the solid constituents in the two cases would have been less marked, the average ratio being 120.134.-P.H.B.]

Modifications from the duration of lactation. The milk does not at once arrive at the degree of perfection in which we have previously supposed it; it commences by merely being colostrum slightly modified, from which it borrows the yellow tint, and the elements

the

Corpus des

of which it retains, gradually getting rid of them in proportion as • Size of Col the period of delivery becomes more distant. For a few days after delivery, and especially before the establish- Estium mih ment of the febrile reaction, known under the name of milk fever, the milk contains, besides its proper elements, albumen, granular bodies, and mucous, either uniting together the globules of butter, or presenting itself under the form of globules. A great inequality in the size of the globules of butter is observed, some of which, according to the happy expression of M. Donnè, are as dust compared to others which are enormous.

It is to the presence of the colostrum that the first milk owes the Celestun purgative property which renders it suitable to rid the child of the meconium; but it is probable that we ought, with M. Lassaigne, to attribute this laxative effect to the fatty matter, being more abundant, and at the same time less completely divided.

Nothing is very positively known as to the period at which the milk ceases to be mixed with the colostrum; this term varies according to different circumstances, which it is not easy to appreciate; sometimes the milk has already acquired all its apparent qualities, when the microscope still shows the presence of granular bodies. Before the end of the first month, the milk should have acquired all its characteristics, and, according to Deyeux and Parmentier, the proportion of caseum should always increase, in proportion as the period of delivery the with becomes more remote.

This proposition does not entirely agree with the results of the analysis of MM. Vernois and Becquerel. According to these experimentalists, it is rather the proportion of sugar which is observed to increase with the age of the milk.

We cannot here misunderstand the final cause which places the food of the child so perfectly in relation with its requirements.

The following is a table, courteously intrusted to me by MM. Vernois and Becquerel, of the analysis of milk at different ages in healthy nurses; it will confirm what has just been observed. The first table represents the modifications of the composition of the milk from one to fifteen days old, and the second, the modifications which take place in the milk from one to twenty-four months old.

a

true chur

247714