2i)0 T r u e and H u n k e 1 , The Poisonous EflFect Exerted etc. 



bases and salts on livmg organisms lias yielded results of great- 

 est import to both chemistry and biology. 



This relation was first demonstrated experimentally by a long 

 series of experiments on plants by K a h 1 e n b e r g and T r u e. ^) These 

 authors, though confining tbeir experiments to a higher type of 

 plants (Lupimis albus L.), recognized the wide ränge of phenom- 

 ena for which this theory furnishes an explanation and pointed 

 out from the data of other experimenters the adequacy of this 

 theory to explain the action of antiseptics. At a later date, 

 Kahle nb er g and True^) presented in greater detail tbeir 

 results published previously in the preliminary article cited. At 

 the same time, Heald, who had repeated the work of these authors 

 with other test plants {Pisum sativum^ Zea mais and Cucurbita 

 pepo), published results confirming the conclusions obtained by 

 these authors.^) 



Some three months later Paul and Kroenig,*) following 

 the same line of argument, showed by experiment that the ex- 

 tension of this theory to explain the action of antiseptics, as had 

 been indicated by Kahlenberg and True, was amply justi- 

 tiable, 



The general principle being established for salts, acids and 

 bases, it was believed by the writers that the extension of this 

 method of study to that class of bodies known as phenols might 

 lead to interesting results. This group of Compounds lends itself 

 also to the study of a further question, the specific influence of 

 chemical radicles. 



Methods. 



Our problera has been to test on living plants the action 

 during short periods of time exerted by phenols of various com- 

 position in Solutions of varying degrees of concentration. In 

 each case we have sought to establish the greatest concentration 

 of each Compound which will permit radicles of Lupinus albus 

 immersed in it to live and make unmistakable growth. Lupines 

 were germinated according to the usual method. From the stock 

 of material at band, plants of healthy appearance were selected 

 and with India ink marked with lines 15 mm from the root tips, 

 a clistance sure to include the eutirc growing zone of the root. 

 Thcy were then fastened in a convenient manner in beakers con- 

 taining the aqueous Solutions of the desired substances at the 

 desired concentrations. Gare was taken, of course, to keep the 

 cotyledons out of the Solutions. Usually four radicles were nsed 

 in each experiment. 



*) Kahlenberg and True. On the toxic action of dissolved salts 

 and their electrolytic dissociation. (Journ. Am. Med. Assoc. July 18, 1896.) 



^) Kahlenberg and True. On the toxic action of dissolved salts 

 and their electrolytic dissociation. (Bot. Gaz. XXII., Aug. 18ft6. p. 81.) 



') Heald, F. D. Toxic effect of acids and salts upon plants. (Bot. 

 Gaz, XXII, Aug. 1896. p. 125.) 



■*) Paul und Kroenig. Ueber das Verhalten der Bakterien zu 

 rlieniischen Reagentien. (Zeitschr. f. physik. Chemie. XXI, Nov. 1896. p. 414.) 



