f72 
Number of the solution. AMEÈB INCMRED: | E: 
Amount of KOH xX 100 000. 40. | 40. | 40. | 40.440; 
Amount of KNO, *X 100. Z..\. 8..| 49. MORE 
Number of tubes in which an amassing | | 
is seen. 62| 4,103; 
result for the graphical representation. | @ : X° |} X | X | O 
We must draw the attention to the fact, that by the 
judging of the result in each of the tubes an absolute 
amassing and a rather distinct amassing at the bottom 
were looked on as a positive result, while the formation 
of a slight amassing and no amassing at all were judged 
to be a negative result. With the help of the example 
we can now easily denote how the average was reckoned 
out. Solution À with 0.07 normal KNO, gave a positive 
result, solution E with 0,11 normal gave a negative result, 
while B, C and D denoted transition-cases; 0,07 normal 
and 0,11 normal are the limiting concentrations, while. 
0:07 F0;11 
2 
be the critical concentration. 
Now we must tell beforehand that we should not put 
too great a value on the absolute amount of the concen- 
tration. In the preceding chapter we already pointed to 
this fact in connection with the way, in which the solutions 
X 1 normal = 0,09 normal is considered to 
were composed. With the exception of this way of pre- 
paration of the solutions, the absolute value of the limiting 
concentrations is of comparatively small importance, since 
for various cultures, especially for cultures from periods, 
which differ greatly as regards light and temperature, the 
limiting concentrations for the same salt and at the same 
acidity can run widely apart. In the preceding chapter I 
drew special attention to the fact, that, with the proceeding 
followed for the same culture, Ï was not troubled by 
