Mr. Swain. 
368 DISCUSSION : FORESTS, RESERVOIRS, AND STREAM FLOW 
passes first over the forested area and later over the deforested area, 
both of which are about equally distant from the junction of the two 
streams. On account of the fact that the rainfall has been somewhat 
held back in the forested ‘area, the flood coming down stream, A, is 
retarded and arrives at the junction at the same time as the flood 
coming down stream B, from the deforested area, which received the 
storm later, whereas, if the forest were cut down, the flood from A 
might have reached and passed the junction before the flood from B ar- 
rived. If this is argued as a demonstration that the cutting down of 
forests would benefit the streams, it is only necessary to reply that, 
on the contrary, it is equally an argument that the deforested area of 
B should be reforested. Besides, how would it be if the storm were 
moving in the other direction? 
B (a) 
Forest 
Fie. 5. 
Or, to take another instance, suppose two streams have their head- 
waters in a region, a, from which the run-off reaches the junction, b, 
in about the same time from both streams, as in Fig. 5.. In this case 
a heavy rain at the headwaters, a, may result in a violent combination 
of floods at b. If, however, the forests along stream A were cut down, 
the water might reach b via stream A before it reached it via stream B, 
and so the flood might be distributed at b. It is thus no doubt possible 
to conceive of cases in which the destruction of a particular forest 
might reduce a certain flood at a certain point, but to conclude that the 
resultant effect of forests is not beneficial is clearly illogical, for (in 
Fig. 5), the clearing of the water-shed of A will increase the violence 
of floods on that stream, while there may be little or no damage due to 
a heavy rise at b or below; and, furthermore, if the storm, instead of 
being stationary as just imagined, is moving, as it always-is, then a 
movement as indicated by the arrow would have the effect that the 
