I& ° Analyses of Books. [March, 
. ^ ie deadly nostrums used by Toffana and Keli, and afterwards 
impaitcd to M. de Sainte Croix and his paramour, the infamous 
adame de Brinvilliers, seem to have been not mere arsenic, 
but to have contained a peculiar ptomaine, which, according to 
oelmi, is formed when animal matter decomposes in contadt 
with arsenical solutions. One method of preparing such a poison, 
not mentioned in the text, was to dose a bear with arsenic, sus- 
pend him by his hind legs, and colledt the liquid which issued 
rom his mouth and nostrils during his death-struggles, or, as 
others say, during putrefaction. 
In what may be called the practical part of the work Mr. Blyth 
discusses systematically the various known poisons, expounding 
them chemical nature, their mode of action, the symptoms pre- 
ceding death, and the appearances presented on post mortem 
examination, as well as the most approved methods of separating 
such poisons from the contents of the stomach, the urine, the 
livei, biain, matter vomited, &c. Illustrative cases are also 
given and— a very important feature— the attention of the expert 
is called to possible lines of defence and to questions likely to be 
raised by the opposite side. 
Space will not permit us to do more than notice the section on 
animal poisons. Great merit belongs here to Mr. Blyth for the 
part he has taken in proving that snake-poisons are not ferments, 
capable of reproduction and multiplication in the blood or the 
tissues of the victim, but true, definite, chemical compounds, or 
mixtures of such compounds. As a matter of course germicide 
agents are utterly useless as antidotes. Dr. Shortt, as well as 
t e author, had long ago found that potassium permanganate, 
recently recommended by Dr. Lacerda as an antidote, is in- 
effectual. 
Concerning cantharides an interesting fact is brought promi- 
nently under notice. These insects may be eaten with impunity 
by the hedgehog, by fowls, turkeys, and frogs ; but a man, a cat, 
or a dog may be poisoned by eating the flesh of animals which 
have thus fed upon cantharides. 
The French “military surgeons in Algeria often meet with 
cystitis among the soldiers, caused by eating frogs in the months 
of , and J une ’ the fr °gs living in these months almost exclu- 
sively on a species of cantharides.” 
In a case of poisoning by cantharides in any country where 
these or kindred inseefls occur, this faefl would suggest a line of 
defence not merely plausible, but possibly well-founded. 
The ptomaines are treated as fully and thoroughly as the 
present state of knowledge admits. None of these bodies, it is 
conceded, has been sufficiently studied. A needful caution is 
given against reliance upon the potassium ferrid-cyanide test. 
