Deposits from the Mediterranean 



239 



depth here was only 782 fathoms, and the land drainage is 

 insignificant. 



TABLE V. Treatment u-ith Hydrochloric Acid, (a) A weighed 

 quantity of the substance was placed in a porcelain basin and 

 100 c.c. of 20 per cent, hydrochloric acid added. The basin 

 was placed on a water-bath and evaporated to dryness. It was 

 then placed on an air-bath and heated so as to convert any 

 soluble silica into the insoluble form. Then it was treated with 

 hydrochloric acid and filtered. The precipitate was weighed, 

 and called the "residue." 



(b) The "residue" was fused with potassium-sodium 

 carbonate, and the silica determined in the usual way. 



TABLE VA. Determination of Fe 2 O 3 and A1 2 O 3 in 



Hydrochloric Acid Solution of Table V. 



Table VA. I-^tinmfinn of Iron and Alumina. Tin- 



tin- tiltr.itr fmin tin- in- ]ul>lr ic^i<luo) was 



pero\Mi-r(l \\ith pdt; ium -hlnr.it-. .ml .minmnia was added 

 till th> pivripitatr locaDy l'iiii.-,| WM \ r\ v|,,\\ in <1 



