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homologue of the former. They found the new hydrocarbon 
to be identical with one already known, which was dis- 
covered by Kekule and Franchimont, and called Triphenyl- 
methane CH(C 6 H 5 ) 3 as it is marshgas or methane, in which 
three atoms of hydrogen are replaced by three phenyl- 
groups. Hemilian, who afterwards obtained the same 
hydrocarbon by a different method, examined it more fully 
and found amongst other results that concentrated nitric 
acid converts it into the trinitro-compound C 19 Hi 3 (N0 2 ) 3 ; E. 
and 0. Fischer prepared the same body, which by the action 
of nascent hydrogen was converted into a base having all 
the characteristic properties of leucaniline. This was heated 
with arsenic acid, in order to abstract hydrogen by oxida- 
tion, and the rosaniline which formed the starting point of 
their last investigation was obtained again. 
From these results it follows that commercial rosaniline 
consists principally of the base C 20 H 19 N 3) and is probably a 
derivative of pseudotoluidine, while the rosaniline from 
paratoluidine and which has therefore been called para- 
rosaniline is its lower homologue, having the formula 
C 19 H 17 N 3i The rosaniline which we obtained from aurin 
is undoubtedly identical with the latter,* its formation 
being readily explained by the following equation : — 
C 19 H 14 0 3 + 3NH 3 = C 19 H 17 N 3 + 3H 2 0. 
The question which now has to be solved is how to ex- 
plain the formation of aurin ; we have already made experi- 
ments in this direction and obtained interesting results, 
which, however, are not yet sufficiently worked out to 
publish them. 
Another question to be elucidated is, what is the chemical 
constitution of aurin ? According to E. and 0. Fischer that 
of pararosaniline is C u H n (NH 2 ) , from which it follows that 
* Since this was written E. and 0. Fischer prepared some pure aurin 
according to our directions, and converted it into a leucorosaniline, from 
which they also obtained triphenylmethane (Deutsch. Chem. Gres. Ber. 
XI., 473). 
