VOLUME LV NUMBER 4 
THE 
DOTANICAL GAZETTE 
APRIL 1913 
THE EFFECT OF CERTAIN CHLORIDES SINGLY AND 
COMBINED IN PAIRS ON THE ACTIVITY 
OF MALT DIASTASE! 
Lon A. HAWKINS 
The effects produced by single inorganic salts in aqueous solu- 
tion upon an organism and the modification of these effects by the 
presence of other salts has been the subject of considerable research. 
It has frequently been found that a definitely toxic influence of one 
Salt may be completely removed by the addition of a second salt, 
itself also markedly toxic when used alone. This mutual counter- 
action by salts of the toxic influence of each other has been termed 
antagonism. While single’ salts and their combinations do not, 
of course, affect all organisms in the same way, yet different 
investigators have shown antagonistic salt action in the case of 
Many organisms and with many chemical compounds. Thus, 
Loew? demonstrated that the i injurious action of certain concentra- 
tions of magnesium nitrate upon Spirogyra majuscula is inhibited 
by the presence in the medium of a proper amount of calcium 
nitrate. Similarly Logs? found an antagonism to exist between 
the nitrates of calcium and of sodium in their influence upon the 
* Botanical contribution from the Johns Hopkins University. No. 23. 
* Loew, O., Uber die physiologischen Functionen der Calcium- und Magnesium- 
Salze im Piteneendeginianne. Flora 75:368-304. 1892. 
3 Lors, J., Studies on the physiological effects of the valency and possibly the 
electrical charges of ions. I. The toxic and antitoxic effects of ions as a function of 
their valency and possibly their electrical charge. Am. Jour. ~~ 6411-433. | 
Tg02, 
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