Jan. 3, 1916 
Hourly Transpiration Rate on Clear Days 
631 
graphs in the late afternoon the two curves tend to reach the night level 
at about the same time. 
distribution or transpiration in relation to solar radiation 
In Table XXXVI is given a summary of the data represented by the 
radiation and transpiration graphs shown in figure 16. The second 
column of this table shows the relative radiation received by the different 
Rig. 15. —Graphs showing the hourly transpiration values of alfalfa for short periods in June and in October, 
with the hourly values of the cyclic environmental factors, all plotted in percentage of the maximum 
or maximum range. 
crops, giving in arbitrary units the integrated area bounded by the 
radiation curve and the time axis. The integrated transpiration obtained 
in a similar manner is given in the third column. In the fourth column 
is given the ratio of the integrated transpiration to the integrated radia¬ 
tion for each particular crop. 
17208°—16- A 
