XXVIII. Researches on the Phosphorus-Bases. 
By Augustus William Hofmann, LL.D., F.R.8., and Augustus Cahoues, F.C.S. 
Heceived June 13th, — Read June 18th, 1857. 
In a note on the action of chloride of methyl upon phosphide of calcium, communi- 
cated more than ten years ago to the Institute of France*, M. Paul Thenaed pointed out 
the existence of a series of bodies which correspond to the compounds of phosphorus 
with hydrogen, which may, in fact, be viewed as hydrides of phosphorus, the hydrogen 
of which is replaced by an equivalent quantity of methyl. 
One of these bodies, a liquid possessing a most offensive odour, spontaneously inflam- 
mable and explosive in the highest degree, corresponds to the liquid phosphoretted 
hydrogen, and appears to occupy, in the phosphorus-series, the same position which 
belongs to kakodyle among the arsenic-compounds. It is a colourless, somewhat viscid 
liquid which boils at about 250° C. Exposed to the slow action of the atmosphere this 
liquid is converted into a compound which is strongly acid and easily crystalhzes. 
This acid is probably analogous to kakodylic acid. 
In addition to this liquid body, two solid substances are formed by the action of 
chloride of methyl upon phosphide of calcium. One of these, according to M. Paul 
Thenaed, corresponds to the solid phosphoretted hydrogen, whilst the other, which is 
the principal product of the reaction, constitutes the hydrochlorate of a very volatile 
phosphoretted base. From its composition this body may be viewed as ammonia, in 
which the nitrogen is replaced by phosphorus, whilst methyl is substituted for the 
hydrogen. When repeating these experiments in the ethyl-series Paul Thenaed arrived 
at similar results, to which he however only briefly alludes. 
At the time when these experiments were first made, the ammonia-bases had not 
been discovered, and the subject presented obstacles so numerous and varied that the 
researches of this chemist remained unfinished. Nobody will be surprised at this, who 
has made himself acquainted with the difficulty of effecting the above-mentioned reac- 
tions, and who from his own experience knows the danger which attends the preparation 
of these compounds, and the horrible odour which some of them possess. 
Paul Thenaed’s remarkable researches did not excite, at the time of their publication, 
that degree of interest which they really deserved. There were but few facts known, at 
that period, with which his results could naturally be connected ; indeed, until after the 
ammonia-bases were discovered, the importance of the experiments on these phosphorus- 
bodies could scarcely be recognized ; then it was that M. Paul Thenaed’s investigations 
* Oomptes Eendus, t. xxi. p. 144, and t. xxt. p. 892. 
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