With respect to ammoniacal dissolution, which I will briefly mention, a rod
composed of an alloy of copper and silver was experimented upon, the copper
becoming entirely dissolved and precipitating itself on the platinum
electrode, the whole of the silver remaining suspended to the positive
electrode in an aborescent form. Arsenide of zinc was similarly treated,
the arsenic becoming precipitated in like manner on the platinum electrode.
Various other alloys, being experimented upon, gave similar results.

I may also, in the last instance, mention that I have found the above
methods of electro-dissolution peculiarly adapted for the preparation of
unstable compounds such as stannic nitrate, potassic ferrate, ferric
acetate, which are decomposed on the application of heat, and in some
instances have succeeded by the following means of crystallizing the
resulting compound obtained.--_Chem. News_.

* * * * *




A NEWLY DISCOVERED SUBSTANCE IN URINE.


Dr. Leo's researches on sugar in urine are interesting, and tend to correct
the commonly accepted views on the subject. Professor Scheibler, a chemist
well known for his researches on sugar, has observed that the determination
of the quantity of that substance contained in a liquid gives different
results, according as it is done by Trommer's method or with the
polariscope. As sugar nowadays is exclusively dealt with according to the
degree of polarization, this fact is of enormous value in trade. Scheibler