BY MEANS OF THE RADIOMICROMETER. 



23 



The data for the two hydrated salts (zinc nitrate and calcium 

 chloride) are recorded in tables 10 and 11. The last three columns 

 of table 10 contain triplicate results for 20 mm. of water, while the 

 last three columns in table 11 contain triplicate results for 10 mm. of 

 water. To save time, we proposed to determine carefully the trans- 

 mission curve for 20 mm. of water, and then use the results in our 



TABLE 8. Depth of cell 20 mm. Transmission of hydrated salts. 



