134 AGRICULTURE. 



knowledgment of M. Perthuys, of the French In- 

 stitute, that " to determine these proportions with 

 the necessary exactness is impossible." Fortunate- 

 ly, however, the pride of science is more affected 

 by this failure than the interests of agriculture. 



Milk is reducible to two species : that of rumina- 

 ting animals, and that of animals which do not ru- 

 minate. Milk of the first description abounds in 

 cream and in curd, that of the other in sugar and 

 whey ; and it is on this distinction that the milk of 

 cows, sheep, and goats is principally employed for 

 the purposes of the dairy, while that of mares and 

 asses is, with similar propriety, yielded to the ser- 

 vice of medicine.* 



Observation has shown that this secretion is much 

 influenced by circumstances of weather, of aliment, 

 and of age. A stormy day lessens its quantity and 

 alters its quality; bad or deficient food has a sim- 

 ilar 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 se- 

 cretion, and soft, nourishing aliments, easy of diges- 

 tion and in sufficient quantity, make it redundant. 



A fact established by the labours of Messrs. De- 

 yeux 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 premised 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 the 

 form of a white and liquid oil. This suspension is 

 the effect of the saccharine matter and the curd, 

 which are among the component parts of milk. 



* The medical uses of asses' milk have come down to us 

 from Hippocrates and Galen. The milk of mares is only estab- 

 lished in the pharmacopoeia of Tartary, where, according to the 

 reports made by travellers, it is food, physic, and brandy. 



