400 
Lincoln—Electrical Conductivity. 
The trichloride of antimony was obtained by passing anhy¬ 
drous chlorine over metallic antimony contained in a retort 
which was gently warmed. The chlorine was dried in the man¬ 
ner described above. The product was then distilled and this 
distillate redistilled, during which process all necessary precau¬ 
tions to exclude the moisture of the air were observed. 
The cupric chloride was prepared in a manner analogous to 
that employed in the preparation of the chloride of iron. 
Stannous and aluminium chlorides were prepared by passing 
dry hydrochloric acid gas over the respective metals which were 
contained in hard glass tubes. The hydrochloric acid gas was 
prepared by dropping concentrated hydrochloric acid into con¬ 
centrated sulphuric acid, and then drying it by passing the gas 
through a train consisting of three bottles containing concen¬ 
trated sulphuric acid and a cylinder filled with fused calcium 
chloride. 
The trichloride of bismuth was prepared by Professor Kahlen- 
berg by treating the hydroxide of bismuth with concentrated 
hydrochloric acid, evaporating the solution to a thick paste 
and thus volatilizing a large portion of the excess of the hydro¬ 
chloric acid. The residue after cooling was finally broken up 
and tranferred to a Berlin porcelain retort and purified by dis¬ 
tillation. 
These chlorides were all pure and perfectly anhydrous; and 
every precaution necessary to keep them so was employed. 
Arsenic trichloride was prepared by treating arsenious acid 
with dry hydrochloric acid gas in a retort and then distilling 
the product. This distillate was redistilled, and had a very 
constant boiling point. 
The stannic chloride used was an anhydrous product from 
Schuchardt. The phosphorus trichloride from Kahlbaum was 
redistilled and that portion taken that gave a constant boiling 
point. 
A C. P. sample of manganous chloride from Merck was re¬ 
crystallized several times and then heated for several days in 
an air bath at a temperature of about 100° C. It was then 
thoroughly pulverized in a mortar and returned to the 
bath, where it remained for about two days longer. C. P. 
