DE. A. W. HOEMANN ON THE PHOSPHOEUS-BASES. 
527 
I have also made a few experiments on the action of dibromide of ethylene upon 
triethylstibine. The reaction is slow, and required long-continued digestion at tem- 
peratures higher than that of boiling water. The tubes invariably contained much gas, 
and the product of the reaction proved to be an inattractively complex mixture of several 
compounds, many of them secondary, which by no means invited me to a more minute 
examination of this process. I omit to quote the few platinum- and chlorine-determi- 
nations which were made, since they do not admit of a simple interpretation. 
In performing the experiments on the arsenic-bases I have been most ably assisted by 
my nephew. Dr. P. W. Hofmann, to whom I express my best thanks for his active 
cooperation in this part of my inquiries. 
The experiments carried out in the ethylene-series, develope clearly enough the nature 
of the diatomic bases, and their relation to the monatomic compounds. I have worked 
with predilection in this series because the accessibility and manageableness of the 
material gi’eatly facilitate the unravelling of the often complicated reactions. There 
could be no doubt that the phenomena observed in the ethylene-series would likewise 
be reproduced in other homologous series. But as a general view of the nature of this 
group of bodies had been gained from the observations recorded in the preceding para- 
graphs, it appeared scarcely necessary to corroborate the results already obtained, by 
many further experiments, which would have been more or less mere repetitions of the 
former. Nevertheless I have, in certain cases, likewise drawn other groups into the 
circle of my observations. Some of the fragmentary results at which I thus arrived I 
will here briefly communicate. 
METHYLENE-GEOUP. 
In another place * I have mentioned an experiment I had made in the hope of convert- 
ing iodoform into iodide of carbon, which, however, had yielded nothing but the di-iodide 
of methylene, discovered not long previously by Boutlerow. As a considerable quan- 
tity of this interesting compound (the result of these experiments) was still at my 
disposal, I took the opportunity of examining more particularly its behaviour to triethyl- 
phosphine and the ammonias in general. 
The methylenated derivatives of the phosphorus-bases will be more conveniently 
examined in connexion with another class of compounds, to which a special chapter of 
this inquiry must be devoted. I will therefore only briefly mention in this place, that 
I have succeeded in producing several of the bases belonging to the methylene-group. 
The members of this series present some peculiarities, distinguishing them in a marked 
manner from the corresponding ethylene-compounds. 
PEOPYLEI^E- AND AMYLENE-GEODPS. 
The experiments in the propylene- and amylene-groups were instituted almost at the 
beginning of this investigation, at a time when the reaction between triethylphosphine 
and dibromide of ethylene had not yet been sufficiently disentangled. The removal of 
* Journal of the Chemical Society, vol. xiii. p. 65. 
