2 
ORIGINAL COMMUNICATIONS. 
ated. And this fresh preparation, too, has been required in 
the same breath in which we are told that not a moment's 
time should be lost in the administration. 
Having contributed in some measure to the continuance 
and extension of this belief, in a table of poisons and antidotes, 
prepared for the General Therapeutics of Prof. Dunglison, 
published in 1S36, it appears to be my particular duty to dis- 
abuse the pharmaceutic and medical public of this impression, 
and to show that the fresh preparation of the hydrate of per- 
oxide of iron as an antidote to arsenious acid, is not necessary, » 
and that any such view of its character is unsustained by sound 
philosophy or experience. 
It is not necessary that the various authorities for the use 
and successful employment of this antidote should be here re- 
viewed to establish its value. Enough has already been 
shown in other journals to satisfy the most incredulous, 
and it is only necessary to refer those who may yet need in- 
formation on that score, to the contents of this Journal, Vol. 
10, page 263, and the American Journal of the Medical Sci- 
ences, Vols. 15, 16, 20, 23, 24,* for experiments and cases 
which must prove fully satisfactory. Considering, then, its 
value as an antidote established by these records, let us exa- 
mine the substance chemically, and see in what manner its 
character, composition, or properties can possibly be so al- 
tered by age or exposure, that its use would be rendered 
fruitless. It consists of iron combined with oxygen, and in 
those proportions, too, in which of all others these substances 
delight to combine. Into which combination, not only iron 
itself, but all its compounds containing less oxygen, sponta- 
neously pass, when exposed to the air for any length of time; 
in other words, when kept. This state of oxidation, then, is 
that in which it is not difficult to retain the metal, and is one 
* Vol. 15, page 537, reported by Drs. Bunsen and JBerthold. 
" 16, " 239, » » Prof. Orfila and Dr. Leger. 
" 20, " 222, « " Mr. John Robson, 
" 23, " 503, » » Dr. John Murray. 
" 24, " 243, " « Dr. Deville. 
