REVIEWS 49 



one might expect to find did not materialize, (^ne result, however, on 

 this point worthy of note is the fact that the conservation of snow, 

 both on the basis of quantity and duration, was shown very clearly to 

 vary directly with the density of the forest. For instance, a forest 

 with a density of 0.49 conserved 4.4 inches of snow for two weeks, 

 while a forest with a density of 0.77 conserved 27.8 inches of snow 

 over a period of four weeks. These figures are, of course, averages 

 for a larger number of stations of approximately equal density. 



On the whole, the study seems to have been very carefully planned 

 and carried out, and it is a very welcome addition to our meager knowl- 

 edge of the subject. The men who carried out the instrumentation 

 are to be commended for their perseverance and tenacity, for dovibtless 

 they encountered many difficulties in taking these observations. The 

 reviewer spent the greater part of one winter taking similar observa- 

 tions on Pikes Peak and can appreciate the hardships and physical 

 difficulties often encountered in work of this nature. One important 

 criticism which we cannot help bringing to the reader's notice is the 

 short period over which the study was carried out. A certain class of 

 scientists, who sometimes like to willfully distort things, or at best 

 throw huge obstacles in the way of the forester who is w'orking on 

 forest influences, may easily raise the objection that the results are 

 based upon too meager data and may easily be accounted for either on 

 the basis of wholly accidental differences in local distribution of pre- 

 cipitation or on the basis of residual and uneliminated errors of meas- 

 urement, which are known to be very large for snow. We do not mean 

 to say that the reviewer would take this attitude, but professional 

 meteorologists might. Therefore studies of this nature should, in 

 order to clear away all intentional or unintentional doubt, be based 

 upon many years of observations. 



Also, it seems that the results here tabulated are a little too much 

 abbreviated. We should like to know, for example, how the density 

 of the forest was measured; also, perhaps some notes upon the condi- 

 tion of the soil at dift'erent periods, as regards to the depth of frost in 

 the forest and in the open. The latter would have an important bear- 

 ing upon percolation and surface run-off and thus be applicable in 

 irrigation. 



We are glad, however, to note the application of the results obtained 

 to the irrigation problem, so important upon the areas tributary to 

 these watersheds. Expressed in irrigation terms, the figures mean 

 that on areas studied the average square mile of forest land retained 



