46 Milk and Its Products. 



Fjord^s control apparatus. — This apparatus, in- 

 vented by the late Professor Fjord, of Denmark, 

 estimates the fat by measuring the solidified cream. 

 Glass tubes similar to those used in the oil -test 

 churn are secured in a frame and a measured quan- 

 tity of milk put in each. The frame holding the 

 bottles is then whirled in a centrifugal separator 

 frame till the cream is completely separated and 

 brought together in a compact mass. This re- 

 quires about forty -five minutes. The solid mass 

 of cream is then measured with a scale and the 

 fat estimated from it by means of a table con- 

 structed by the inventor. This apparatus is in 

 very common use in Denmark, but has never been 

 introduced into this country. 



Development of milk tests in the United States. — Up 

 to the year 1888, there had been no apparatus devised 

 which would determine the fat in milk accurately, 

 easily, cheaply and quickly. None of the methods 

 described could in any sense supph' the place of the 

 gravimetric analysis, even for commercial purposes. 

 The oil -test churn came the nearest to it, but that 

 was of no use for milk, and at this time the separa- 

 tor creamery was beginning to supplant the gathered- 

 cream factory, and the demand was constantly 

 stronger for a means of determining the fat in milk. 

 This year also marked the establishment of the na- 

 tional grant to Agi'icultural Experiment Stations in 

 each of the states, and one of the first problems at- 

 tacked by the chemists of these stations was to de- 

 vise a quick method for the determination of fat in 



