232 Forestry Quarterly 



chapters of especial interest to American foresters are: I. 2. In- 

 direct Benefits of Forests; III. 3. Yield; III. 5. Upkeep and Im- 

 provement of Forests ; III. 8. Reforestation. 



In the preface Henry quotes Pliny to the effect that "The for- 

 ests render us thousands of services, without which life would be 

 impossible." When one reads Jacquot's enumeration of the in- 

 direct benefits of forests Pliny's broad statement seems no exag- 

 geration. In outlining his summary to Part I, Chapter 3, the 

 author states, "We will then study their influence on the meteoro- 

 logical factors which regulate climate, the flow of rivers, the pub- 

 lic health, the aesthetic and military manoeuvers." Under (1) 

 "Moisture-Rainfall" he states that "Forests increase the average 

 annual relative humidity of the air" and supports this statement 

 by citing instances where forests increased the humidity 16 to 20 

 per cent and where deforestation brought on water famines : 

 "Sicily, Malta, the islands of Maurice, Reunion, and Cap Vert 

 suffer from terrible droughts since they were deforested." He 

 even goes so far (perhaps too far) as to say that "rainfall varies 

 according to the per cent of forested area." Could this be scien- 

 tifically proved? The generally accepted statements that forests 

 diminish (2) hail, (3) decrease frosts, and protect from (4) wind 

 are repeated but without such definite illustrations as are given 

 under (5) "springs." Here the author gives interesting illustra- 

 tions which have not appeared in American forest literature. 

 "The towns of Rome, Vienna, and Constantinople, the village of 

 Saint-Amarin (Alsace) . . . lost their springs after the defores- 

 tation of ravines where they rose. ... At Claveizolles and at 

 Lamure-sur-Azergues (Rhone) whenever the coppice was cut 

 the springs fell. In Sardinia the springs have gone dry on all 

 points where the mountains were denuded." 



Jacquot traces the beneficial effect of forests on (6) avalanches, 

 (7), (11) soil, (8) floods, (9), (10) rivers, (12) sand, (13) 

 climate, (14) health, (15) depopulation, (16) military move- 

 ments (especially now that scouting is by aeroplanes), and (17) 

 "Esthetique." This glance at chapter 2 illustrates the complete- 

 ness of the work. 



Somewhat more detailed than the usual book on "Elements of 

 Forestry," it is of especial value to students and teachers of 

 forestry. T. S. W., Jr. 



