20 
Dr. Wollaston on metallic titanium. 
sembling that of the gallate, that I do not think any difference 
that I can discern is to be depended upon as constant. It 
differs from prussiate of copper by inclining to orange instead 
of purple, while the colour of prussiate of uranium is rather 
brown than red. 
Since the oxide thus examined agrees in its characteristic 
properties with that of titanium procured from Anatase, I 
cannot entertain a doubt as to the general nature of the sub- 
stance under consideration. I believe it to be pure, for I find 
no trace of any other substance combined with it, not even 
of iron, although the crystals are found imbedded in an iron 
slag, in the presence of metallic iron ; nor yet of silica, for 
which the oxide has a strong affinity. Neither is there any 
sulphur present, as the salt which remains after oxidation of 
it by nitre, contains no trace of sulphuric acid. 
That the cubes are in the metallic state, is nearly proved 
by their lustre, by the effect of nitre upon them, and by the 
failure of borax to act upon them, till they have been sub- 
jected to the action of nitre. It may be farther observed, 
that, when the action of nitre is rapid, heat is evidently ge- 
nerated, as by the combustion of other metals ; but as I acted 
upon them in their solid state, and did not pulverise them, I 
did not witness what could properly be called detonation, as 
described by Lampadius. 
The property which may be regarded as most decisive of 
the metallic state of these cubes, is the power which I find 
them to possess of perfectly conducting the most feeble elec- 
tricity. 
If a slip of zinc and another of copper be placed in contact, 
and immersed together in dilute sulphuric acid, bubbles of 
