216 CHYMISTRY APPLIED TO AGRICULTURE. 



resource for variety in the food of the inhabitants of the 

 country. But as these preparations cannot be preserved for 

 any length of time, it is necessary to find some means of 

 keeping them free from alteration, or so to moderate and 

 govern decomposition, that the food furnished by the case- 

 ous matter may be varied, and the power of keeping it pro- 

 longed : this object is obtained in the fabrication of cheese. 



The existence of whey in curd hastens most powerfully 

 the action of putrid decomposition ; and, in order to pre- 

 vent or retard this change, it is necessary that the whey 

 be forced out by mechanical power. Those cheeses Avhich 

 are the best dried, may be preserved the longest time ; in 

 order to hasten the drying, the curd is carefully kneaded, 

 and in some cases the cheese is exposed to heat or to a 

 strong pressure. 



The period during which cheeses can be kept maybe 

 prolonged, by impregnating them well with salt ; this is 

 done in the following manner : when the curd has ac- 

 quired the requisite degree of consistency, the surface of 

 it is furrowed and covered with pounded salt ; the next 

 day the cheese is turned, and the same operation perform- 

 ed upon the other side of it. This salting is repeated till 

 every part of the cheese is well seasoned, it is then placed 

 upon a bed of straw, and turned from time to time. The 

 straw upon which cheeses are placed, must be frequently 

 changed, and the planks washed, and in every part of a 

 dairy the greatest cleanliness and neatness should be ob- 

 served. 



The surface of a new cheese gradually loses its white 

 appearance under the above treatment; the size is diminished, 

 and there is formed an external crust harder than the middle, 

 and having a sharper and less agreeable taste. 



When the caseous matter is precipitated from milk re- 

 taining its cream, the cheeses formed from it are not so 

 dry as those which consist entirely of the caseous part ; 

 their taste is mild and their substance more mellow and 

 unctuous. 



Independently of the modifications which cheese is sus- 

 ceptible of, from the addition or suppression of cream, the 

 mixture of different kinds of milk varies it greatly. I for- . 

 merly remarked that the milk of the sheep and goat was 

 softer and more viscous than that of the cow ; this renders 

 the cheese made from it mellow, besides its possessing a 

 very agreeable flavor. The most celebrated cheeses are 



