2 Journal of the Asiatic Society of Bengal. [N.S., XVI, 
tory. The Calcium chloride, obtained from Merck in granular 
form was spread on three dishes and introduced quickly in the 
case which was then sealed up. It will be noticed (Diagram I 
and Table I, Column III) that the rate of leak on the aver- 
age was more than double the maximum value. After about 
140 hours, on opening the case, it was found that the Calcium 
inefficient as a desiccant for electrostatic work has already 
been noticed in Glazebrook’s Report ! of 1891 on the Muirhead 
standard air-condenser (capacity about 6:02 M.F.) as the 
following passage will show :—‘The amount of leakage was 
very different .... and depended on the dryness of the air 
and ebonite pillars. Thus on March 11, when strong acid had 
been enclosed for some time, the leak per minute amounted 
to ‘1 per cent. of the whole charge. The sulphuric acid was 
Diagram I 
Calcium chloride (12.11.14—-18.11.14). 
ts/min,. 
} 
LS) 
—~ Leakage in vol 
=) 
3 , j 
— Time in hours a nd a ze 
removed during the Easter vacation and replaced by Calcium 
chloride, and after this the leak rose to about 1 per cent. per 
minute o or ten gimes its former value. With the Calcium 
Te seems worthwhile to draw special attention to the 
unsatisfactory behaviour of Calcium chlor ide, as this sub- 
stance still seems to be occasionally iy hi under the im- 
pression that it improves electrical insulation 
II. Mrratutc Soprom. 
Metallic sodium is eneeeabat used as a erent in 
A. Reports on Electrical standards, page 376. 
: Foe instance, Richardson, Proc. Roy. Soc., Vol. XCII, page 42. 
