ILLINOIS DAIRYMEN'S ASSOCIATION. 245 



by what process or for what purpose it was used — it may have 

 been for commercial utilization or food products — it made its 

 first entry into the market more than fifty years ago. 



All the processes are based upon the simple principle of 

 making curd by means of natural acidity of the sour milk or by 

 the use of rennet. Later on all kinds of vegetable, organic and 

 even mineral acids were employed, which, however, in my opin- 

 ion, are decidedly detrimental to the product in question. Es- 

 pecially where the curd is used for the manufacture of pure 

 "Casein" and the remaining whey for sugar of milk, it is es- 

 sential to know which method should be employed. The fol- 

 lowing extracts from chemical authorities will support my state- 

 ment. 



In the second German edition of "Muspratt's Practical 

 Chemistry," 1870, is mentioned that "The 'Casein' or 'Lactarin' 

 is due from milk by its own fermentation, and was at that time 

 supposed to be started by the fermentation of lactic acid in 

 milk." 



An English translation of "Wagner's Chemical Techno- 

 logy," published in 1872, I found the following passage : "The 

 application of a mixture of lime has been recently proposed as 

 a mordant for this purpose 'Casein,' which is known in Eng- 

 land as 'Lactarin,' and prepared from milk, (of which it is the 

 curd), is dissolved in diluted caustic amonia ,and the solution 

 thus obtained is mixed with freshly prepared milk of lime. The 

 Casein lime mixture is used for steeping the cloth intended to be 

 dyed. The Casein-lime becomes insoluble by the application 

 of heat, after which the fabric is so thoroughly mordanted that 

 it resists washing with alkaline fluids." 



The following we find in "Thorpsesis Dictionary of Chem- 

 istry," Vol. 1, published in 1890 : "A preparation of 'Casein/ 

 known as 'Lactarin,' is used as a substitute for albumen in dye- 

 ing calico printing. It was introduced by Pattiscn in 1848, for 

 fixing pigment colors." 



Other German books are mentioning" the use of "Casein" 



