ABSORPTION OF CORNSTALK TISSUE 
125 
Since most of the measurements upon absorption in similarly 
prepared colloidal mixtures have been upon ' the basis of an in- 
crease in thickness, it was thought that: aS' long as the weighing 
method was used in the present study, it would be desirable to 
see how the two forms would correspond. 
In Table I, a summary is given of a number of determinations.' 
It will be noticed that there is a cornparatively close agreement. 
TABLE I. COMPARISON OF THE PERCENT AGB OF ABSORP- 
TION BASED UPON AN INCREASE IN THICKNESS AND UPON 
AN INCREASE IN WEIGHT 
Time Immersed 
2 Days 
9 Days 
Weight 
Thickness 
Weight 
Thickness 
Agar water 
3022 
3011 
3463 
3338 
Agar NaOH.......— — — 
1392 
1613 
1966 
2270 
The data given in Table II show the diferences in the total 
absorption. 
TABLE 11. THE TOTAL ABSORPTION IN PERCENT FOR CORN, 
AGAR, AGAR AND EGG ALBUMEN 
Water 
. Sodium Hydroxide 
Citric Acid 
Corn 
863 
851 
583 
Agar 
4072 
2105 
1706 
Agar and egg albumen. 
3921 
2002 
3457 
The accompanying graph, (Fig. 25), shows the comparative 
rate of absorption. The first weight was taken after four hours 
and cannot be distinctly shown on the diagram. The early in- 
crease in weight cannot be entirely attributed to absorption. This 
early increase is greater and continues for 20 hours in the con- 
structed colloids while for the corn tissue it is much less. It is 
a rather striking feature that the maximum point of swelling 
for each medium is reached at about the same time in the different 
solutions. For example, the maximum amount of swelling of 
agar, agar and albumen, and corn tissue in sodium hydroxide 
is practically reached in 39 days. The curves show many sim- 
ilarities in the rate of absorption, as for example in sodium 
hydroxide the rather rapid hydration ends in four days. After 
19 days there is very little gained. The same general close rela- 
tion holds true with water. Agar and albumen in citric acid 
is a notable exception in correlation. This shows a rapid, nearly 
equal rate of absorption so near as to fall within the range of 
