1896 | TOXIC ACTION OF DISSOLVED SALTS 123 
73. META-NITRO-BENZOIC ACID. 
(Begun January 16, 3 P.M.; closed January 17, I P.M.) 
Concentration 
gm. mol. per liter Length Remarks 
eao0 20.55" dead 
eae 16,0:°:** a 
T2800 36.0 “ apparently normal 
oe es 26.67" ody = 
74. PARA-NITRO-BENZOIC ACID. 
(Begun January 16, 6 P.M.; closed January 17, 12 M.) 
Concentration 
gm, mol. per liter Length Remarks 
svou 17.0™ flabby, dead 
ges 17.0 “ +“ “ 
efo0 Zt.0."" dead 
sae. 19.0 beg «5 
raton - 50 ae apparently normal 
eee he 33.0 “ ““ “ 
That the modern theory of solutions would throw light on 
their physiological action was to be expected. From the fore- 
going detailed results it is evident that in the case of plants the 
toxic action of solutions of electrolytes, when dissociation is 
Practically complete, is due to the action of the ions present. 
When dissociation is not complete, the undissociated part of the 
electrolytes may also exert a toxic effect, as has been pointed 
out in several instances. We have here then, as it were, a rec- 
eles of the theory of electrolytic dissociation by the organic 
orld, 
Mr. F. D. Heald, Fellow in Botany at the University of Wis- 
fonsin, has investigated the action on other plants of a consid- 
crable number of the solutions which we have tested. The 
results that he obtained are presented in an accompanying 
Paper. They are perfectly analogous to those that we have 
found, and hence strongly confirm our conclusions. 
