358 On a New Metal, Pelopium, 
On comparing this behavior of the yellow chlorid with that 
observed on treating a mixture of pure tantalic acid and charcoal 
with chlorine, I obtained a perfectly similar yellow chlorid anda 
white non-volatile residue ; but the quantity was far smaller, and 
its production could be entirely avoided, if, in the preparation of 
the chlorid of tantalium, every trace of humidity and atmos- 
pheric air had been carefully excluded. Moreover, the sublimed 
yellow chlorid from the Bavarian mineral, very much resembled 
the chlorid of tantalium. This similarity likewise extended to 
the acids prepared from the two chlorids; they behaved so much 
alike, that it was only after long-continued investigation that 
properties were discovered by which they might be separated. 
In the preparation of chlorid of tantalium from the tan- 
talic acid from the Finland tantalite, and especially in that of the 
yellow chlorid from the Bavarian mineral, I frequently obtained 
considerable quantities of a red chlorid, which was still more 
volatile than the yellow one, and proved on examination to be 
the chlorid of tungsten. When the chlorids are exposed for some 
time to the air, the tungsten can be removed by digestion with 
ammonia, as soluble tungstate of ammonia. ; 
Sometimes chlorid of tin and chlorid of titanium were obtain- 
ed in preparing the chlorid ; they could be readily distinguished, 
by their fluid state of aggregation, from the other chlorids. 
The formation of the chlorids of tungsten and tin appears Te 
markable, inasmuch as the acids from which the chlorids were pre- 
pared had been kept in a moist condition for a long time in con- 
tact with sulphuret of ammonium. I draw especial attention to 
this circumstance, because, unless perfectly freed from these 1m- 
purities, the chlorids and the acids prepared from them are ob- 
with very different properties. 
~ The yellow chlorid from the Bavarian mineral differs, there- 
fore, principally from the chlorid of tantalium by its leaving 8 
white non-volatile residue on its production, or rather on its vol- 
atilization, at a high temperature. This residue consists princi 
pally of the acid which may be obtained from the yellow chlo- 
rid by decomposition with water. ; 
In the preparation of the yellow chlorid from the columbite 
of Bodenmais, there is formed along with it an oxychlorid, whit 
is decomposed by heat into chlorid and acid, just like the tungs 
tate of the chlorid of tungsten. The formation of the OxXY~ 
chlorid can be prevented by placing a long layer of charcoal 12 
the anterior portion of the glass tube, in which the mixture OF 
acid and charcoal is to be treated with chlorine. While the chlo- 
rine is passing through the tube, this charcoal is first raised to a 
strong red heat, and then the mixture. es 
The acid of the yellow chlorid from the Bodenmais mineral, 
ch is contained in it along with the niobic acid, I have named 
