446 APPENDIX. 



waters of each affluent must ultimately be reflected in the flow 

 of the main river. The temporary retention of large amounts 

 of water and eventual change into subterranean drainage 

 which the well-kept forest floor produces, the consequent 

 lengthening in the time of flow, and especially the prevention 

 of accumulation and carrying of soil and detritus which are 

 deposited in the river and change its bed, would at least tend 

 to alleviate the dangers from abnormal floods and reduce the 

 number and height of regular floods. 



Concerning the moisture of the soil the results of the most 

 recent experiments differ. Ramann, in 1895, published a se- 

 ries of results which indicated that the soil of the forest may 

 be even drier than that of the neighboring open land. This 

 view he finds strengthened by experiments made in small 

 clearings within the forest, where he finds the soil of the 

 sunny side of the clearing and that of the old forest itself 

 decidedly drier than the soil of the shaded part of the clear- 

 ing, though he also finds the soil under a young bush cover 

 more moist than that under old timber. 



Whether a forest cover aids in the accumulation of ground 

 water by improving the permeability of the soil was made the 

 object of an experiment by Wollny, in a series of inconclusive 

 small pot experiments which led this investigator to the ques- 

 tionable result that bare land was more conducive to percola- 

 tion than ground covered either by grass or trees. This 

 would surely be true only if the bare ground, as in the experi- 

 ments, is kept in an artificial, not natural, condition. 



Attempts to deduce the influence of forest on waterflow 

 from wholesale measurements and observations have been 

 made in this country by Vermeule, of New Jersey (see 

 Proceedings American Forestry Association, Vol. XI, pp. 

 130-137, and report of New Jersey Geological Survey, 1894). 

 and Rafter, of New York (Proceedings of American Forestry 

 Association, Vol. XII, pp. 139-165, and report of State engi- 

 neer and surveyor of New York, 1896), the former claiming that 

 no appreciable influence existed, the latter calculating the influ- 



