Specific Rotation. 
1914-15.] 
The Optical Rotation of Sugars. 
43 
/3-Lactose. 
This sugar was prepared by the method of Hudson (^7. Amer. Chem. Soc., 
1908, XXX, 960). The crushed crystals were found to have density L600 
at IS"", whereas ordinary lactose, the a-form, has density 1‘534. 
