232 
INDEX 
Pages 
Definition of — Continued 
e, vapor-pressure potential 8 
E x 8 
Ei 9 
Ei, Evaporation from land 16 
E w , Evaporation from water 16 
flood-flow 139 
freezing-melting period 166 
/, rise of lake surface 9 
I c , run-off into lake. Constant part 9 
It, rise of mean lake surface 9 
Ii, rainfall on lake surface 9 
7j, inflow into lake 9, 1 1 
J«, outflow from lake 9, 11 
normal stream-flow 136 
v, residual 9 
w. wind travel ." 9 
/ w \ 
I TpjTj - x I , wind term 9 
x, minimum wind travel which affects 
evaporation 9 
Delaware River 216 
D/ and —D. Example of computation of . . . . 179-180 
D f and (n—G) 
estimating dates to use in computation of . 182-184 
Dix River 216 
Z>„. Example of computation of 179-180 
Effect 
of seiches on absolute term of evaporation 
observation equations 80 
of winds of small velocity on evaporation. 
Evidence from Solution V s 93, 94 
of winds on lake surface 22 
of winds on water levels at Harbor Beach . 22-23 
of winds on water levels at Mackinaw . . . 22-23 
of winds on water levels at Marquette . . 23 
of winds on water levels at Milwaukee . . 22-23 
Elevation 
Lake Michigan-Huron, observed mean 
daily, 1909-1913 52-72 
Lake Michigan-Huron, observed mean 
daily, 1909-1913, corrected for 
winds and barometric effects . . . 52-72 
Ei and E% adopted values of final 82 
Equation 
observation (see observation equation) 
flood-flow. Form of 139 
Equation of normal stream-flow 
additional adjustments to 166-168 
form of 135-139 
of Stream B 170-171 
Error systematic 86 
Estimate of 
I c for Lake Michigan-Huron 17-19 
I c for Lake Superior 17-19 
stream-flow. Rules for applying this 
method 226-228 
Estimating dates to use in computation of Dj 
and (n-G) 182-184 
Evaporation 
a linear function of wind velocity above 
10.8 inches per hour 99-103 
accuracy of computed 121-122 
curve is not concave upward. Evidence 
from Solution BBi 94 
curve, Lake Michigan-Huron. Computed 
from results of Solution Vi 96-97 
curve, Lake Superior. Computed from 
results of Solution BB 2 94-96 
curve. Shape of, as estimated from resi- 
duals of Solutions BBi and V s . . 94-96 
Pages 
Evaporation— Continued 
daily, from Lake-Michigan-Huron, 1909- 
1913 52-72 
final seven least^square solutions for de- 
termining 90-92 
formula. Comparison of one developed 
in this investigation with others . 122-129 
formula. Final one derived in this in- 
vestigation 82-84 
formula. Other evidence in favor of 
adopted 98-99 
formulas. Conclusions on comparison of . 129-130 
formula developed in this investigation. 
Comparison with 
Abassia's, Fitzgerald's, Car- 
penter's and Stelling's 126-129 
Freeman's 122-126 
Horton's results 126 
Meyer's 122-126 
from land. General formula 136-137 
from water. Definition 83-84 
Lake Michigan-Huron, amounts of 84-85 
Lake Michigan-Huron. Comparison with 
observed fall of lake surface .... 84-90 
Lake Superior. Results from Solution 
BB t 90 
land, Ei 
definition of 16 
estimate of, case 1 17 
case 2 18 
case 3 18 
minimum wind which affects 90-102 
definition 9 
first approximation to 93-97 
normal equations, Lake Michigan-Huron. 
Final ones 80-81 
normal equations, Lake Superior. Final 
ones 81 
not affected by small winds, as judged by 
Solution Vi 93-94 
observation equation 
examples of computation of known 
quantities in final form of 25 
final form of, used for determining . . . 8-9 
Lake Michigan-Huron, 1909-1913 . . 73-80 
pan 83 
solutions. Principal facts from final ones 
on Lakes Michigan-Huron and 
Superior 81 
water, E w . Definition of 16 
estimate of, Case 1 17 
Case 2 18 
Case 3 18 
Watershed B 207-210 
Evaporation and run-off 
entanglement between 118 
lake Michigan-Huron. Final normal 
equations 11 1-1 12 
observation equations. Example of 110-111 
Example of 
normal equations, flood-flow, Stream B. . 174-175 
observation equations for 
adjusting S c and R i0 167-168 
flood-flow 172-173 
substitution in observation equations for 
flood-flow 177-178 
Example of computation of 
barometric correction, daily 33, 41 
barometric effect, hourly 40 
— D, Stream A 151-154 
decrease in rate of melting 159 
D/and —D 180-182 
