Diagram No. 9 
Conparison of the half monthly mequality mn tune from observation and hy theory. 
See ; Se ee sy Sa Sis SE i ae, Re is a 
i a ea cy + 2 way BOS Bhs Feed e Ben 4 ety a tame eax 1 
fit eae Wee i | oA t 
| Sia Seve | i / i i if Re 
Belden eeeeee occ 
#1 i ie } | 
+ Sia + 4} fp 4 to BO Gas oO Sa 4 
pity Z / i 
_ From the formulas 
.— — — from observation (mean curves) 
