362 MILK. 
product of the combustion of animal substances 
containing an albuminous or caseous consti- 
tuent. € proportion of cream contained in 
milk from the human subject has been deter- 
mined by Sir Astley Cooper at from one-fifth 
to one-third by measure, varying with the 
health, the food, the habits, and state of mind 
of the mother. The colostrum or first milk 
which is observed in the human breasts has 
been examined by Meggenhofen. He states 
that it contains more saline matter than the 
after milk, and describes it as having the ap- 
pearance of a weak solution of soap containing 
oleaginous particles. It is very prone to be- 
come sour and decompose, and becomes viscid 
by exposure to the air, hence its name from 
xorAAwuas, to agglutinate. 
Several instances are on record of the exis- 
tence of milk in the male breasts, and the ana- 
lysis of a specimen lately | spigeree by Mayer 
in Schmidt's Jahrbucher, July 1837, is as fol- 
ows :— 
Fatty matter... ...... 1.234 
Alcoholic extractive .... 3.583 
Watery extractive ...... 1.500 
Insoluble matters ...... 1.183 
Total solid contents .... 7.500 in 100 
parts of the fluid. 
It was slightly alkaline. The following were 
the physical properties of this milk: when left at 
rest it quickly coagulated, and cream soon sepa- 
rated; after some hours butyraceous globules 
collected on the surface. Its specific gravity 
was 1024. 
Milk from several of the herbivorous Mam- 
malia has been examined by Stiptrian, Luiscius, 
and Bondt, with the following results :— 
The milk of the ass has a specific gravity of 
1.023 to 1.0355; it yields a white and light 
butter which is very apt to become rancid. 
The caseous matter does not separate so easily 
as in cow’s milk; the whey, however, can be 
obtained very clear, and is found to contain 
more sugar of milk than that from the cow. 
An analysis yielded the following result : 
reaM ...+.+e++- 2.9 per cent. 
ee Pe eee mare 
Sugar of milk .... 4.5 ,, 
The milk of the mare has a specific gravity 
of 1.0346 to 1.015; it yields but little cream, 
but contains a very large proportion of sugar; 
the analysis gave : 
0.8 percent. of cream, 
7) oe caseous matter, 
and 8.75 _,, of sugar of milk. 
The milk of the mare, as also that obtained 
from the ass, very rapidly commences the alco- 
holic fermentation, an effect which cannot be 
produced but with the greatest difficulty in 
cow’s milk. 
Goat’s milk has a specific gravity of 1.036; 
it possesses a very disagreeable odour of the 
animal, and the more strongly so if the goat 
be dark-coloured ; it yields a large quantity of 
cream and butter; the latter contains, in addi- 
tion to the usual acids of butter, a peculiar 
acid to which the name of hircic acid has been 
given; it is to this principle that goat’s milk 
owes its peculiar unpleasant odour. This milk 
contains also a large quantity of caseous matter 
of a firm dense character. Payen found goat’s 
milk composed as follows : i 
Butter .eccsescsecccecees 4.08 
Casein er eeeee eee ennee evree 4.52 
Sugar, salts, and extractives.. 5.86 
Water ...ccccccccssccess GOO” 
Stiptrian, Luiscius, and Bondt 
7.5 per cent. of cream, 4.56 of butter, 9.12 
casein, and 4.38 per cent. of sugar from the 
milk of a goat. 
The milk of the sheep has a specific gravity 
of 1.035 to 1.041; it yields a larger propor- 
tion of cream: the butter is semifluid and 
yellow in colour; it putrifies very easily. Thi 
milk yields 11.5 per cent. of cream, 5.8 of 
butter, 15.3 of caseous matter, and 4.2 per 
cent. of sugar of milk. 
The milk of the bitch and also of the por- 
poise have been lately examined by Dr. Bird; 
the former contained 15.8 per cent. of a 
and 7.2 of butter mixed with some sugar 
milk. That from the porpoise contained 23.00 
per cent. of oily matter, and a volatile ingre- 
dient supposed to be phocenic acid. The 
cific gravity of bitch’s milk is stated at 1.024. 
The milk is very prone to become contami- 
nated by various ingesta; that of the cow is 
frequently impregnated by the odours derived 
from particular pasturage, and if saffron or in- 
digo mixed with their diet the milk has 
been observed to assume more or less the 
colour of those pigments. 4 
Chevallier, Henry, and Peligot made expe- 
riments on the milk of asses to whom several 
different substances had been exhibited ; t 
were enabled to detect the oxides of iron . 
zinc, the trisnitrate of bismuth, common salt, 
and sesquicarbonate of soda with great ease ; 
sulphate of soda required to be administered in ~ 
very large doses before it could be detected in 
the milk, and sulphate of quinine could not be 
discovered, though large quantities were intro- 
duced into the stomach. These 
state likewise that the iodide of om 
cannot be detected in the milk unless exhibited 
in doses of upwards of a drachm. This rule, 
however, cannot apply to the human subject, 
as I lately very readily detected it in the milk 
of two of my patients, one of whom had taken’ 
only 45 grains of the iodide in divided doses 
of 5 grains each, administered three times a day 
for three days; and the other 105 grains in 21 
doses of 5 grains each, administered in like 
manner. It is probable that many substances 
enter the milk which the ype state of 
mistry does not admit of our detecting, and 
every practitioner is aware of the danger in- 
curred to the child by or any 7 
medicine to the mother during the period 
lactation. ae 
There is perhaps no animal secretion which 
bears so strongly-marked an analogy with the 
blood as the milk, and which promises us so 
fair a prospect of discovery in the mysteries 4 
of secretion, and we cannot but hope that as” 3 
animal chemistry advances we may be able to_ 4 
imitate those changes which occur in the minute _ 
