PROFESSOR ROSCOE’S RESEARCHES ON VANADIUM. 
3 
(2) The following vanadium oxides have been obtained both in the dry and wet way, 
and their compositions determined : — 
*(1) V 2 0 2 , vanadium dioxide, or divanadyl . . . . = 134-6 
(2) V 2 0 3 , vanadium trioxide (Berzelius’s suboxide) = 150-6 
(3) V 2 0 4 , vanadium tetroxide = 166-6 
(4) V 2 0 5 , vanadium pentoxide (vanadic acid) = 182*6 
(3) The so-called terchloride of vanadium (V Cl 3 . V=67‘3) contains oxygen ; it is an 
oxychloride having the formula V O Cl 3 (V=51-3) ; it may be called vanadyl tri- 
chloride, or vanadium oxytrichloride, and corresponds to P O Cl 3 , phosphorus oxy- 
chloride. 
(4) Three other solid oxychlorides exist, having the composition 
(1) V O Cl 2 , vanadyl dichloride, or vanadium oxydichloride. 
(2) V O Cl, vanadyl monochloride, or vanadium oxy monochloride. 
(3) V 2 0 2 Cl, divanadyl monochloride. 
(5) All the native vanadates are tribasic : — 
( a ) Vanadinite from Zimapan, analyzed by Berzelius (Pogg. Ann. Bd. xxii. p. 63), 
contains nearly three equivalents of lead oxide to one of vanadium pentoxide. 
(b) Eusynchnite, analyzed by Czudnowicz (Pogg. Ann. Bd. cxx. p. 27), contains 
three equivalents of a mixture of lead and zinc oxides to one of vanadium pent- 
oxide. 
(c) Arceoxene, analyzed by V. Kobell (Journ. fur. Chem. Bd. 1. p. 496), was found 
to have a similar composition to eusynchnite. 
( d ) An American vanadinite, analyzed by Smith (Journ. Pr. Chem. Bd. lxvi.p. 433), 
is a tribasic compound. 
(e) Dechenite from the Pfalz is, according to Brush (Sill. Am. Journ. series 2, 
vol. xxxiv. p. 116), identical with Arceoxene, and therefore a tribasic compound. 
if) Volborthite, according to Credner’s analysis (Pogg. Ann. Bd. lxxiv. p. 546), 
also contains one of vanadic acid to three of basic oxide. 
(6) Vanadic acid fused with sodium carbonate displaces three molecules of carbon 
dioxide, showing that normal or ortho-sodium vanadate is tribasic, the formula of 
this salt being Na 3 V 0 4 . 
(7) The so-called monovanadates are salts corresponding to the monobasic phosphates, 
and may be termed metavanadates ; thus, Na V 0 3 , NH 4 Y 0 3 , Ba 2 V 0 3 . The 
so-called bivanadates are anhydro-salts, similar in constitution to the anhydro-salts 
of chromic and boric acids. 
* [I had originally intended to call the first and third oxides vanadium monoxide and dioxide respectively, 
giving to these substances the simplest empirical formulae Y 0 = 67*3 and Y 0,=83 - 3, as it is as yet uncertain 
whether the molecular weights of these oxides, in accordance with the law of even atomicities, are multiples of 
the above, or whether, as in the only similar case, that of the nitrogen oxides, they are represented by the 
above numbers themselves. Acquiescing in the opinion expressed by several chemists that the former alternative 
is the most probable, I have now adopted the names as they stand in the text. — Jan. 20, 1868.] 
