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resistance which the H-ions experience from the small 
quantities of sodium acetate, while the second bend can 
be attributed to the resistance of the salt by the H-ions. 
It is a very important fact that in alkaline solutions 
there is found the additivety of the influence of base and 
salt while this does not hold for the combined influence 
of acid and salt. À corresponding phenomenon is observed 
in the conduct of proteïns towards base and salt and acid 
and salt. In a publication of Hardy on colloïd solutions 
of globulins this phenomemon is discussed at great length 
(Hardy, 1905). 
Globulins are ampholytes, they can form compounds 
with acid and base. Globulin solutions can be floceulated 
by neutral salts. 
In this respect they show characteristic qualities. Every 
salt gives a precipitation by a slight concentration and 
also by a great concentration. By a moderate concen- 
tration the salts cause solution. By a slight concentration 
the salts only act on globulin combined with base or acid. 
The action of the salts is in this case corresponding to 
that on suspensoïds; the colloïdal parts are charged elec- 
trically and are discharged by the ions of the salt, which 
contain an opposite charge. Plurivalent ions have more 
influence than univalent ions. By great concentrations the 
salts act upon combinations of globulin with salt, which 
give colloïdal parts without charge. 
In this case we can make a comparison with the salting 
out of emulsoïds. The concentrations which Hardy used 
when studying the flocculation of the globulins by small 
quantities ol electrolyte and their dissolving again by 
average salt concentrations can be compared to the con- 
centrations, which have an influence on the motility of 
Chlamydomonas. 
It is with the experiments on the dissolving of the 
globulins, that Hardy noticed the different conduct 
