282 FORESTS, RESERVOIRS, AND STREAM FLOW 
is worthless. This proposition need scarcely be urged upon the experi- 
enced engineer. For himself he would never place any real reliance 
upon forestry. Called in consultation, for example, in the problem of 
protecting the City of Pittsburg from floods, he would be bound to 
take as his measure of the problem the highest recorded flood on the 
river with a good factor of safety on that, and then figure out by what 
methods—artificial reservoirs, levees, raising of grades, or clearing the 
river channel of artificial obstructions—he would obtain the desired 
relief. He would not dare, as the physician in the case, to advise 
his patient that he could dispense with or lessen in any degree the 
application of the remedies proposed, nor save one dollar of the cost, 
by anything that might be done in reforesting the water-shed of the 
rivers themselves.* 
In like manner no engineer could honestly advise lowering in 
height by a single inch the levees of the Mississippi because of any 
possible application of forestry to the water-shed of that stream. And 
again he could not advise that forestry development would lessen in 
any degree the cost of improving the rivers for low-water navigation. 
Engineers fully understand their responsibility in these matters. But 
great engineering projects cannot be carried out without money, and 
the people will not give the money unless convinced of the necessity 
and wisdom of the plan proposed. So long as there is apparently some 
easier and simpler plan, some panacea, no matter how nebulous or 
unproven, that offers a way out without the expenditure of so much 
cold cash, they will be backward in voting money, and the counsel of 
the engineer will be of no avail. Hence the complete divorcement of 
forestry from any connection with river regulation—so far, at least, 
as its effect upon the cost of such regulation is concerned—will be a 
distinct and positive gain to the latter. 
In the second place, forestry will be left to work out its own 
salvation without any reference to the rivers. Will not its cause be pro- 
moted by this divorcement? At first thought it may seem that thereby 
one great argument for forestry is lost; but no argument can be of 
*Possibly the writer is too positive in this opinion. He finds that, in one case 
at least, the City of Williamsport, Pa., reputable engineers have advised reforesta- 
tion of mountain slopes as a protection against floods. The statement of “an emi- 
nent authority” was cited with approval to the effect that ‘four-fifths of the precipi- 
tation is detained by the surface of the ground” under forest cover. But here, as 
in all these assumptions, the rule applies only to the average condition. The point 
is overlooked that in periods of heavy precipitation the retentive capacity of the 
forest bed becomes exhausted. If the City of Williamsport is relying upon this 
advice it is certainly laying up for itself a season of repentance. 
