34^ POISONS : THEIR EFFECTS AND DETECTION. ‘ [§ 407 . 
1 mgrm. of morphine sulphate on a water-bath, yields a blurred strych¬ 
nine reaction when the residue is dissolved in sulphuric acid, and a 
crystal of potassic permanganate added. But still there is evidence 
whereby to suspect the presence of strychnine. 
“ A solution of 2 mgrms. of morphine sulphate treated in like manner 
with 0-01 mgrm. of strychnine yields like results. 
“ A solution of 3 mgrms. of morphine sulphate evaporated to dryness, 
with a solution of 0-01 mgrm. strychnine, yielded results with the potassic 
permanganate test the same as if no strychnine was present. 
“ A solution of 1 mgrm. of morphine sulphate, treated as above, with 
a solution of 0-1 mgrm. strychnine, offered positive proof of the presence 
of the latter.” 1 
Dragendorff was able to render evident 0-025 mgrm. mixed with 
twenty times its weight of quinine sulphate ; the same observer likewise 
recognised 0*04 mgrm. of strychnine in thirty-three times its weight of 
caffeine. Yeratrine is likewise not injurious. 
Para-nitro-benzoic acid produces in solutions of strychnine, even in 
dilutions 1 : 4000, quite peculiar crystals, first short strongly double 
refracting crystals, from each of which, after a time, grow bristles and 
hairs, like the pappus of the Compositse. 2 
Dinitro-resorcin is also an excellent test for strychnine ; on addition 
of the reagent to a solution of strychnine salt, the solution remains clear 
for an hour or more, according to dilution, but ultimately well-formed 
fine bundles of large, red, centrally grouped needles separate. 3 
§ 407. The physiological test consists in administering the substance 
to some small animal (preferably to a frog), and inducing the ordinary 
tetanic symptoms. It may be at once observed that if definite chemical 
evidence of strychnine has been obtained, the physiological test is quite 
unnecessary ; and, on the other hand, should the application of a liquid 
or substance to a frog induce tetanus, while chemical evidence of the 
presence of strychnine was wanting, it would be hazardous to assert that 
strychnine was present, seeing that caffeine, carbolic acid, picrotoxin, 
certain of the opium alkaloids, hypaphorine, some of the ptomaines, and 
many other substances induce similar symptoms. The best method (if 
the test is used at all) is to take two frogs, 4 and insert under the skin of 
the one the needle of a subcutaneous syringe, previously charged with a 
solution of the substance, injecting a moderate quantity. The other frog 
is treated similarly with a very dilute solution of strychnine ; the 
two are then placed under small glass shades, and the symptoms 
observed and compared. It is not absolutely necessary to inject the 
1 Fliickiger’s Reactions, translated by Nagelvoort, Detroit, 1893. 
2 Grutterink, Zeit. f. anal. Chemie, 1912. 
3 Rosenthaler and Gorner, Zeit. /. anal. Chemie, 1910. 
4 A very practical disadvantage of the physiological test is the great difficulty of 
obtaining frogs exactly when wanted. 
