1914-15.] Interaction of Methylene Iodide and Silver Nitrate. 231 
are mixed the electrical conductivity is the same as that of N/40 silver 
nitrate, and it does not begin to change until silver iodide commences 
to form; and on adding methylene iodide to N/18*5 silver nitrate the 
conductivity does not change until the double compound begins to 
crystallise out. It would therefore seem that if AgN 03 .CH 2 l 2 exists 
in solution in any large proportion the ionisation is practically the same 
as that of silver nitrate. 
{Issued separately December 3, 1915.) 
