576 
EESEAECHES OE DE. HOEMAIs'X AXD M. CASOTES 
attracted that attention to which they were entitled ; then it was that the remarkable 
parallelism of the compounds of phosphorus and nitrogen, more and more distinctly 
exhibited by these discoveries, began to become an object of general interest to 
chemists. 
It is now many years since M. Paul Thenaed abandoned the study of the phosphorus- 
compounds, for the first knowledge of which we are indebted to him. The unfinished 
state in which these researches remained, and the rich and abundant harvest collected 
since that period in all the neighbouring fields of science, necessitated a re'sision of the 
subject. The discovery of methylamine, dimethylamine, and tiimethylamine, and of 
the corresponding terms in the ethyl- and amyl-series, had showm that the hydi’ogen in 
ammonia may be replaced by binary molecules, such as methyl, ethyl, amyl and phenyl, 
the newly-formed compounds retaining the basic character of the original ammonia- 
molecule ; whilst the production of triethylstibine and triethylarsine had fiumished the 
proof that the total replacement of the hydrogen in the indifferent antimonietted and 
arsenietted hydrogen exalts the chemical character of these compounds in a most 
remarkable manner, the methylated and ethylated bodies exhibiting basic characters 
scarcely inferior to those of ammonia itself. It remained therefore to be investigated 
whether phosphorus, which, by its chemical tendencies, stands between nitrogen and 
arsenic, would exhibit a similar deportment. It remamed to be ascertained in what 
manner the gradual entrance of binary molecules in the place of the hydrogen in phos- 
phoretted hydrogen would change the character of the original compoimd. The dis- 
covery of the tetrethylated ammonium-bases had also opened a new field of research, in 
which the corresponding terms of the antimony- and arsenic-series were rapidly brought 
to light. It was indeed possible to predict with certainty, that an appropriately selected 
method would lead to the production of the analogous derivatives of phosphoretted 
hydrogen. The time for resuming the study of the phosphorus-bases had in fact 
arrived. 
We have been engaged for a considerable time in the investigation of this subject, 
and now beg to offer to the Royal Society in the following pages an account of our 
experiments. 
In the first place, we have endeavoured to obtain the bases corresponding to phos- 
phoretted hydrogen, by a method analogous to that followed by M. Paul Thexaed. 
Recent experience suggested at once the replacement of the gaseous chloride of 
methyl by the liquid iodide, which is so much more convenient for experiment ; 
and also the substitution, for the phosphide of calcium, of the compound of phosphorus 
and sodium obtained by the direct union of the elements. On the application of heat, 
these substances act on one another with great energy, producing combustible and 
detonating compounds, so that the experiment is not without danger. Often the pro- 
duct of the operation is lost ; and \f the reaction has taken place without explosion, the 
separation of the conslituents of the very complicated mixture wiiich results can be 
effected only with the greatest difficulty. 
