MILK. 55 



of remarkably poor milk supplied to the union workhouse, 

 Belfast. Nos. 7 and 8 are examples of rich and poor milk 

 respectively quoted in a recent lecture by Dr. John A. 

 Voelcker ; 9 is an analysis, at Giessen, by Haidlen ; and 

 10 is the average of 12 analyses, at Bechelbronn (Alsace), 

 by Boussingault.* 



These tables, together with the intimation that casein, 

 the essential matter of cheese, is soluble in alkaline solu- 

 tions, and is so held dissolved in milk that the butter of 

 milk is a compound of several oily matters of different com- 

 position, and produced in various proportions, according to 

 such circumstances as the food and the temperature of the 

 period that the sugar of milk is capable of transformation 

 by the mere re-arrangement of its elements into a substance 

 having acid properties, and therefore called lactic acid 

 that this re-arrangement is effected by almost any disturb- 

 ance of a chemical nature, such as the presence of a ferment 

 itself in process of decomposition that, in fact, any sub- 

 stance in contact with it, undergoing chemical transforma- 

 tion, acts as a ferment on it, so that decaying matters in its 

 neighbourhood, and air carrying filthy odours, the product 

 of such decay, are thus ferment enough for the purpose 

 that the curd of milk itself, in the presence of warm air, 

 thus undergoes such chemical transformations, and be- 

 comes a ferment that rennet, itself a ferment [the word 

 may stand, whatever theory of its action be adopted], deals 

 with the solvent whatever it is by which the casein is held 

 dissolved in the milk so as to release the latter, which re- 

 sumes its form as curd insoluble in water : These par- 



* For 1, 9, and 10, see Boussingault's "Rural Economy." Others 

 are taken from the Journal of the Agr. Soc., and Johnston's Lectures 

 on Agr. Chemistry, and Dr. Thomson on the Food of Animals. 



