LIMNOLOGICAL OBSERVATIONS IN THE UPPER MISSISSIPPI. 
367 
Table 7. — Mean velocity and discharge of Mississippi River at different stages, Muscatine, Iowa. 
Date. 
Discharge, 
cubic feet 
per second. 
Mean veloc- 
ity, feet 
per second. 
Date. 
Discharge, 
cubic feet 
per second. 
Mean veloc- 
ity, feet 
per second. 
Aug. 16 1916.. 
41,900 
53, 100 
1.91 
2.40 
May 11, 1914 
81,200 
154,800 
2.87 
Oct. 3, 1914 
Mar. 30, 1916 
During the present investigation measurements of velocity were made only in 
the upper layer of water. The results of observations on the main channel of the 
river are given in Table 8. The velocities observed at low stages of water vary 
from 1.23 feet per second at Red Wing to 2.8 at Fairport. Probably the velocity 
at Rock Island Rapids is considerably greater than was observed, as it was impossible 
to make observations in the swiftest part of the rapids. In the latter part of Sep- 
tember when the river was rising its flow was swifter; the maximum velocity, 4.37 
f. s'., was observed at New Boston (September 20). The current just below Lake 
Pepin is rather swift, reaching 3.29 f. s. on September 10; another measurement 
made 10 days before this showed only 2.05 f. s. at the same station. Since there 
was no considerable change in the stage of the river during these days, the disparity 
may be due to the fact that the section where the current of the outflow of Lake 
Pepin is swiftest is very short, and on the occasion of the two observations the boat 
was not anchored each time at the same point. Only one-third mile upstream the 
velocity of the current observed on the same day, September 10, was 0.77 f. s. 
(See stations 124 and 124a, Table 29, p. 431.) 
Table 8. — Velocity of current measured at different points on the Mississippi River. 
Miles 
from 
St. Paul. 
Stage of 
river on 
the day 
of obser- 
vation. 
Velocity, 
feet per 
second. 
Between Prescott, Wis., and Hastings, Minn 
Below Prescott, Wis 
Diamond Bluff, Wis 
One mile above Red Wing, Minn 
One mile above the head of Lake Pepin 
Lake Pepin 
Reads Landing, Minn 
Opposite mouth of Zumbro River 
Between Winona, Minn., and Homer, Minn 
Four miles above La Crosse, Wis 
Opposite mouth of Root River 
Between De Soto, Wis., and Lansing, Iowa 
Three miles above Prairie du Chien, Wis 
Prairie du Chien, Wis., east channel 
Prairie du Chien, Wis., main channel 
Opposite mouth of Wisconsin River 
One mile below Cassville, Wis 
Four miles below Bellevue, Iowa 
Tliree miles below Clinton, Iowa 
Rock Island Rapids, near Day Mark Pier No. 2 
One mile below mouth of Rock River 
Fairport, Iowa 
Near New Boston, 111 
Near Burlington, Iowa 
Six miles above Dallas, 111 
Six miles above lateral channel 
Four miles above Dallas, 111., Shokokon Slough 
Dallas, IU 
Fort Madison, Iowa 
Nauvoo, 111 
Three and a half miles below Galland, Iowa 
Three miles above the Keokuk drawbridge 
Near the Keokuk dam 
Alexandria, Mo 
40J 
Sept. 2 
Sept, i 
Aug. 29 
. . .do 
/ Aug. 30 
\Sept. 10 
Sept. 10 
.. .do 
Sept. 14 
.. .do 
...do 
Sept. 15 
Sept. 16 
Se|>t. 17 
Sept. 18 
July 12 
/July 13 
\Sept. 20 
/July 14 
\Sept. 20 
July 20 
...do 
July 21 
/July 15 
\Sept. 22 
Sept. 24 
. . .do 
/July 15 
\Sept. 
1.57 
1.57 
1. 38 
1.23 
1.38 
2.05 
3.29 
3. 14 
2.42 
2.20 
2.57 
1.92 
2.49 
3.14 
1 1.46 
2.20 
2.75 
1 Strong south wind. 
2 At Keokuk, Iowa. 
s At Warsaw, Mo. 
