DISCUSSION : FORESTS, RESERVOIRS, AND STREAM FLOW 345 
ing entirely at the stream sources; and it is well known that floods of mr. Toad. 
this character, coming by themselves, are less to be dreaded on the 
lower river than those from any other source. In fact, there are so 
many combinations of flood inception and flow that it is practically 
useless to undertake to deduce theoretical results from data which are 
insufficient and likely to be in error. The result of Mr. Horton’s 
deductions when compared with gauge heights actually reached by 
moderate floods, illustrates the futility of attempting to reduce dis- 
charge to gauge height and vice versa. His results are given in two 
tables: One shows the computed reduction in gauge height at Cairo 
for certain flood years, assuming the reservoirs operative; the other 
gives the computed heights for certain gauge stations below Cairo. 
Mr. Horton’s figures are reproduced here as Tables 7 and 8, with the 
reductions, stated in terms of equivalent gauge heights, added. 
TABLE %.—Amount tHe Maximum Reapina or THE CaiRo GauGcE 
Woutp Be Repucep sy Reservoirs IN THE OnIO River DRAINAGE 
AREA. 
Re duction in gauge height Equivalent gauge height.,* 
Year. at Cairo, in feet. in feet. 
1880 7.0 38.6 
1881 5.0 41.8 
1882 7.0 44.9 
1883 V5 44,7 
1884 8.5 43.3 
1885 7.0 33.0 
1892 6.0 42.3 
1893 6.0 43.3 
1897 7.0 44.7 
* Figures supplied by the writer. 
TABLE 8.—Tue Amount, In FEET, THAT THE CREST OF VARIOUS 
Fioops Woutp Have Been Repucep at DIFFERENT SECTIONS ON 
THE Lower Mississipp1 Hap ONE-THIRD OF THE DRAINAGE AREA OF 
THE OHIO RiveR BEEN CONSERVED. 
Station. 1882. | 1883. | 1884. 1892. | 1893. | 1897. 
6.0 6.0 7.0 
5.5 5.5 7.0 
5.0 5.0 6.5 
6.0 6.0 8.0 
6.0 6.0 8.5 
6.5 7.0 9.0 
Flood* 
stage. 
42.3 43.3 44,7 45 
29.1 29.7 30.6 
40.7 42.9 45.3 42 
43.3 43.5 44.4 42 
Lake Providence.. 35.8 35.8 36.0 36 
Vicksburg..........ceece eens 41.9 41.3 43.3 45 
*Figures supplied by the writer. 
