CHEMICAL LABILITY. 
19 
One of the amidoxims, the benzenylamidoxim 
THTT 
C 6 H 5 —C = n _oh was shown by Mering to be poisonous: 
0,5 g. will kill a dog ; 0,1 g. a rabbit ; 0,03 g. a frog. 1 ) 
But we observe also on the other hand that substances 
acting readily upon labil amidogroups are equally poisonous ; 
above all may be mentioned the formic aldehyde, the free 
cyanogen, and the nitrous acid, which latter is far more poison¬ 
ous than nitric acid. I observed that formic aldehyde CH 2 0 in 
a dilution of 1: 10000 kills readily microbes and algae ; of 1 : 2000 
in 2 hours crustaceans, worms and mollusca. 2 ) Rabbits are killed 
by 0,24g. P ro Kilo. ( Zuntz ). Phaenogams watered with a 1 p. 
mille solution will die in from 2-6 days ( Bokorny ). This aldehyde 
annihilates also as I have found (Jahresber. f. Thierchemie 1888) 
the actions of the enzymes. The action on amines is shown by 
the equation : 
H 2 CO + H 2 N-(z) = H a C = N-(#)+H a O 
The free cyanogen is for lower vegetable and animal organ¬ 
isms a stronger poison than hydrocyanic acid; in a dilution of 
i : 5000 it kills cells of the bear-yeast, in dilution of 1: 10000 
infusoria and algae. 3 ) Its action upon labil amidogroups may be 
represented by the following equation : 
CN 
= NH 
L, — N H — 1 
+ H 2 N-(z) = 
n -NH a 
^ = N-(*) 
■NH -(4 
CN CN CN 
The action of nitrous acid upon labil amidogroups is shown 
by the following equation : 
NO OH + H 2 N-(z) = OH-N = N—(#) + H a O 
and : 
OH —N = N —(*) = OH-W + N ; 
Free nitrous acid in a dilution of 1 :100000 kills algae 
within 48 hours (.Loew and Bokorny 4 )). Nitrites are poisonous 
in all those cases, where nitrous acid is set free by organisms, 
thus for plants containing free acids or acid salts, and for the 
1) Ber. D. Chem. Ges. 1885 p. 1054. 
2) The great antiseptic properties of formic aldehyde were first observed by 
myself. Jahresb. f. Thierchemie 1888. 
3) According to investigations which were carried on by myself and Mr. Tsuka - 
moto in the laboratory of Komaba. 
4) Botan. Zeitg. Dec. 1887. 
