SOME NEW BASES OF THE LEUCOLINE SERIES. 279 
obtaining crystalline salts from the mixed bases was noted; “the double 
chlorides of platinum, gold, cadmium, mercury, lead, and zinc were tried, but 
without success, only resinous sticky masses being obtained.” With the pure 
and isolated bases we have since been able to get crystalline salts. Crystals, 
nearly one-eighth of an inch in length, of the double chloride of mercury and 
tetracoline, were prepared by adding solution of mercuric chloride to solution of 
chloride of tetracoline, and dissolving in hot water the sticky globules that are 
produced, on cooling white transparent crystals of the double chloride 
appear. 
When solution of chloride of cadmium is added to solution of chloride of 
tetracoline a white precipitate of the double chloride comes down. If now the 
contents of the tube be agitated, the precipitate settles on the sides in sticky 
globules of a dark purple colour, which allow of the liquid to be poured off 
and the globules washed. After some days tufts of minute silky crystals shoot 
from and cover the dark globules. Examination of these showed them to be 
the double chloride of cadmium and tetracoline. 
Pentacoline and the higher bases do not appear to form crystalline salts 
with these metals. 
