( wer ) 
» Observation has shown, that this secretion is much, 
influenced by circumstances of weather, of aliment 
and »f age. “A stormy day lesseris its quantity and 
alters its quality; bad or deficient food has a similar 
but greater effect, and the fact is well known, that 
very young and very old cows give poor milk. Mild 
Weather, on the other hand, promotes the secretion, 
and soft nourishing aliments, easy of digestion and 
in sifficient quantity, make it redundant. 
A fact, established by the labors of Messrs. Dey- 
éux and Parmentier, and long before known to the 
dairy maid, is, that the milk first drawn is serous; 
that that which succeeds is less so, and that what are 
commonly called strippings, are nearly all cream. 
‘Having preiised these facts, we proceed to the 
business of butter-making—the theory of which is 
reducible to the following heads: 
1st. Butter is found suspended in milk, in ibe form 
of a white and liquid oil. ‘This suspension is the ef- 
fect of the saccharine matter and the curd, which are 
among the component parts of milk. 
2d. Ina state of repose and ina cool temperature, 
this oily matter separates itself, in a great degree, 
from the serum and curd, mounts to the surface and 
there forms a pellicle of greater or less density. — 
3d. When in contact with atmospheric air, it draws 
from ita portion of oxigen, and thence acquires a 
yellow color and disposition to harden. 
Ath. Agitation and pressure are necessary to sepa- 
Galen. The milk of mares is only established in the pharmacopia of Tartary ; where, 
according to the reperts made by travellers, it is foed, physic and brandy. 
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