On the Physiological Action of 
Amidosulphonic Acid. 
BY 
4 
N. Maeno, NögakushL 
Amidosulphonic acid has been subjected to extended chemic¬ 
al investigations by Dr. Edward Divers , Professor in the Imperial 
University of Japan, and it was he who proposed to test whether 
this substance would prove just as good a source of nitrogen for 
plants as the ammonium salts or whether they would be noxious. 
Dr. Loew then made some experiments which showed that, 
while bacteria and mould fungi could utilise the sodium and 
calcium salts of this acid as soures of nitrogen, and algae are not 
noxiously affected even by i per cent solutions of these two salts, 
higher plants, on the contrary, are noxiously affected by them. 
As this fact was so contrary to expectation, a larger series of ex¬ 
periments appeared desirable, to decide whether such an action 
would generally take place in different groups of phanerogams. 
I therefore made experiments not only with entire plants and 
young branches but also with isolated leaves and with the seeds 
of various species. It is well known that ammonium salts in a 
certain concentration act noxiously upon plants as well as upon 
animals, and that this poisonous nature either decreases or in¬ 
creases in intensity when we substitute one hydrogen atom with 
other groups ; thus, hydroxylamine and diamidogen are more 
poisonous than ammonia, while on the other hand amido-acetic 
Weak poison. 
Strong poisons. 
Not poisonous. 
Nencki has found that carbamic acid exerts a poisonous effect 
upon warm-blooded animals, which is different from the effects of 
the equivalent amount of ammonia. This proves that hydrolysis 
into ammonia and carbonic acid is not readily accomplished by 
acid or taurin are not poisonous : 
NH 3 
NH 2 -NH 2 | 
nh 2 -oh ) 
NH 2 -CH 2 -COOH 
nh 2 —ch 2 —ch 2 —so 2 oh 
