86 
THIRTEENTH REPORT. 
different sizes, such as table, butter, cheese, etc., by means of tubular 
screens or patent separators. To some of the fancy brands of table 
salt small amounts of calcium or magnesium earborate are added to pre- 
vent caking. 
The salt production of the state for 1908, as given by the U. S. Geo- 
logical Survey, was 10,194,279 barrels valued at $2,458,303. This in- 
cludes the brine salt worked up into soda ash and other products. The 
production for the same year as given by the state salt inspector was 
6,247,073 barrels. 
Ann Arbor, Mich., April, 1911. 
