DISCUSSION: FORESTS, RESERVOIRS, AND STREAM FLOW 361 
attached to their establishment. For instance, as no absolute knowl- mr. Harts. 
edge could be obtained of the height of future floods, no ordinary em- 
bankment should be considered as offering absolute security, and the 
riverside owners should understand that bursting of the bank was a 
contingency to be allowed for, which it would be prudent to meet by 
some sort of accident assurance. Further, it. was advisable not to 
make the banks unnecessarily long, because the more scope allowed 
to a flood the less: dangerous it became, and consequently the less scour 
would occur in the river-bed and banks.” 
And M. Malézieux, in his communication on the subject (p. 312), 
stated that about twenty years before, much attention had been 
directed to this means of preventing, or at least diminishing, the effects 
of floods: 
“Vast reservoirs were to be made, kept empty during the dry 
season, in which might be retained the water from heavy rainfalls, so 
that it might be released progressively and at preconcerted times, in 
such a way as to prevent the coincidence and the accumulation of 
the flood water from several rivers of the same basin. It had been 
found, however, that this plan, very simple in theory, would be difficult 
and uncertain in practice, and that it might under some circumstances 
do more harm than good. This was referred to in a paper in the 
‘Annales des Ponts et Chaussées,’ vol. ii. of 1881, p. 6.” 
In spite of its theoretical advantages, we see this reservoir system 
condemned for practical reasons, in several countries, by distinguished 
engineers, after mature study. It is now resurrected and advocated in 
the United States, mainly by men who have had no experience in the 
improvement of rivers for the benefit of navigation or in the practical 
control of floods. They are endeavoring to establish a system theoreti- 
cally designed to combine various utilities, but which, like the com- 
bination tool, “is the joy of the inventor, but the despair of the user.” 
It seems clear that, to justify the high cost, their main efforts will 
necessarily be directed toward producing profitable water-power first; 
then to the secondary benefits, such as the interests of forestry, attempt- 
ing flood control, assisting in the reclamation of flooded. areas, and per- 
haps finally including the improvement of navigation. That our 
rivers would obtain any decided benefit from such a project, or that it 
could be practically applied, needs a more convincing argument and 
more accurate and pertinent facts than any that have been thus far 
advanced. 
Dr. Georce Otis SmitH* (by letter).—Colonel Chittenden’s paper mr. smith. 
on the relation of forests to stream flow is especially suggestive to all 
who have had opportunity to observe forests and streams. It is indeed 
a subject for practical men, and inasmuch as geology, like engineering, 
is a practical science, it may be appropriate for a Fellow of the 
* Director, United States Geological Survey. 
