Permeability 143 
alcohol, on the one hand, and zinc sulphate, cobalt chloride and 
manganese acetate on the other. Antagonism was also observed 
between quinine hydrochloride and copper acetate, and between 
chloral hydrate and copper sulphate. Little or no antagonism was 
found between these compounds and sodium and potassium salts, 
nor between formaldehyde and any salt except aluminium chloride. 
With each organic substance the depoisoning action of the trivalent 
aluminium ion was found to be greater than that of the divalent ions 
examined. 
The antagonism between an aniline dye and an electrolyte was 
also demonstrated by Szucs (1910). The dye selected for most of 
Szucs’ experiments was methyl violet, the intake of which by 
Spirogyra cells was examined by determining the time required for 
the cells to acquire a standard depth of colour. When, for example, 
potassium nitrate was present in a variety of concentrations (o-ooi N 
to 0-08 N) in 00001 per cent, methyl violet solution, the time taken 
for the standard colouration of the cells to be acquired was found to 
vary with the concentration of the salt. The same was the case when 
calcium nitrate or aluminium nitrate was employed. In Table XLVI 
are exhibited the results obtained. 
Table XLVI 
Time taken for cells of Spirogyra to reach a definite intensity of colour 
when immersed in methyl violet solution containing various quantities 
of electrolyte. (Data from Szucs) 
Concentration of 
methyl violet 
in per cent. 
Electrolyte 
Concentration of 
electrolyte 
in normalities 
Time in minutes 
required for the 
acquisition of 
standard tint 
o-oooi 
Potassium nitrate 
— 
2-0 
o-oooi 
o-ooi 
3*0 
o-oooi 
0*01 
5*0 
o-oooi 
19 
0-08 
8-25 
0-0003 
Calcium nitrate 
— 
0-83 
0-0003 
,, 
o-ooi 
2-25 
0-0003 
,, 
o-oi 
8-50 
0-0003 
,, 
0-04 
’ 8-50 
0-0003 
,, 
0-09 
9*17 
0-0003 
Aluminium nitrate 
— . 
0-83 
0-0003 
„ 
0-0005 
8-0 
0-0003 
I, 
0-0025 
12-5 
0-0003 
0 
o-oi 
?ig-o 
Thus the extent of the antagonistic action is dependent both on 
the concentration of the electrolyte and on the valency of the latter. 
