Mr. Chitten- 
den. 
470 DISCUSSION: FORESTS, RESERVOIRS, AND STREAM FLOW 
paper to justify either of these statements. Nothing of the sort was in 
the writer’s mind at all. In another place in his paper, speaking of 
natural reservoirs, he states that “the ground is the most important of 
these, absorbing on the average probably one-third of the total rain- 
fall.” But in discussing the causes of floods he relegated ground storage 
to the background, for the excellent reason that it plays a very minor 
part in such occurrences. The great bulk of the water that makes 
floods is what some one has well called “fugitive” water—that which 
escapes into the streams over the surface of the ground. Time is the 
controlling element in the quantity of water that percolates into the 
earth. A given soil will permit a given quantity to pass through it in 
a given time, and if Noah’s flood were to pass over the surface this 
percolation would not be any faster. Moreover, what does soak into 
the ground may be a long time in returning to the surface through 
springs, and any such portion of a storm plays almost no part in the 
flood which the storm produces. Whatever part ground-water plays 
in a great flood (and it is always a minor part) it is generally from 
precipitation long prior to that which produced the flood, and it cannot 
therefore be well considered when tracing the relation between a given 
storm and the resulting flood. 
Another point in which some of the writer’s critics have found a 
stumbling block is this: that even though the forest bed be filled to 
saturation, still the mechanical obstructions to run-off, the crooked 
and indirect channels, would retard flow more than in the open. But 
in all the writer’s reasoning upon this subject, the superior “retentive 
capacity” of the forest as compared with that of the open country has 
included all these retarding causes in the one that are in excess of 
those of the other; and whenever he has spoken of the forest bed being 
saturated he has meant that whatever difference may have existed at 
the beginning of a storm has been obliterated so that the water reaches 
the streams as rapidly from one class of surface as the other, provided 
they are otherwise similarly conditioned. 
Mr. Leighton makes the following remark in regard to the forest 
bed: “The common understanding is that the forest mulch is not the 
storage agent in any except a merely nominal sense.” It seems im- 
possible that Mr. Leighton can mean this literally, as otherwise he 
would sacrifice the position of both himself and Mr. Pinchot, that the 
forest bed does hold the water of precipitation and give it an oppor- 
tunity to soak into the ground. Indeed, Mr. Leighton not only con- 
tradicts the universally accepted view of forestry advocates, but even 
his own opinion, as expressed on former occasions. On page 7 of 
Forest Circular 148, issued November 7th, 1908, is the following from 
himself and Mr. Horton: 
“The Southern Appalachian forests act as a great storage reservoir, 
and this is done largely through the medium of its humus, the litter 
