328 Scientific Proceedings, Royal Dublin Society. 
towards the area, then the number of impacts, in unit time, is 
U x = where JV is the total number of ions of the proper sign in 
unit volume. Or taking U constant, = KV. 
Now, equal effects are produced by 2” triads, 3 diads, 
6N monads, owing to the charge on each being proportional to 
the valency. Hence if the solutions are of the same concentration 
(i.e. there are the same number of ions in unit volumes of triad, 
diad, and monad solutions), then the electrical effects produced in 
equal times in each solution (7.e. the quantity of free electricity 
brought to unit area) will be in the ratio 
KN” : KK TP ‘ KN’ 
2 Bo be 
If NV be above a certain value in these ratios, the “‘ instantaneous ”” 
7 
K : 
value of — g may represent a quantity sufficient to “ discharge ” 
adjacent suspended particles as effectively as the greater quantities 
= or a . In this case no valency effects will be revealed, 
and the salts will produce sedimentation indifferently as regards 
their chemical nature. 
If the value HW is sufficiently small, the above phenomena 
will not be brought about, and an effect directly proportional to 
the valency will appear; finally, if there exist in the liquid effects 
of a restorative character, 7.e. which continually tend to restore to 
the particles their electric layers, then there will be no effect on the 
sedimentation unless in each case AN is above a certain value. 
It is to be expected that intervening conditions between equal 
flocculation by like concentrations of monads, diads, or triads, 
and those producing no effect on the sedimentation will exist for 
varying strengths of solutions. Again, with increasing fineness 
of the suspension, the flocculative effects of the lower valencies 
will be delayed for the reasons given by Whetham. The finest 
1 In comparing the effects of acids and alkalies, the higher velocities of H and HO 
cannot be left out of account. Similarly, ‘‘the ionic sphere of influence”? must be 
considered greater for H and HO in comparative experiments whether on colloid or 
other particles. 
