174 



Thirty Years of Milling. 



a stone from the well-known Burbage Quarries in Derbyshire ; 

 but while it is perhaps as good a stone as can be procured, it is 

 not in any tangible respect superior to the burrstone used in 

 the Home Counties or the granite used in Cornwall. It will be 

 seen to have forty-two furrows, divided into fourteen groups 

 of three ; each group is called a harp, from its shape. If we 

 were to reduce the number of furrows we should get a closer 

 ground flour, but the gritty surface of the millstone itself is 

 the main thing. The English custom, following that of the 



Romans, who followed that of the Greeks, is to turn the top 

 stone. But the Americans often run the lower stone. As the 

 roller mill has conquered at least as rapidly in the United 

 States as here the advantage of the change is not very 

 apparent. Professor Kick, however, is a deservedly high 

 authority in America, and I understand that in his lectures on 

 millstone milling he has claimed for the under-running (i) better 

 flour, (2) more work, (3) better distribution of feed,- and (4) a 

 quicker removal of meal. The matter is not unworthy of inves- 

 tigation. 



The output of stone mills is increased by the use of exhaust 

 fans, which, by removing the heated air, improve the quality ot 

 the flour, benefit the health of the operatives, and increase the 

 mean rate of grinding, so that stones grinding 200 lb. an hour 

 without an exhaust fan will easily grind 300 lb. with one. 



The progress of roller milling may best be studied in the 

 columns of that well-known technical journal, The Miller, which 

 was established on 1st March, 1875, and contains as its first entry 

 under " Patent Intelligence," the granting, on 16th February, 



