FORESTS AND CLIMATE 325 



rainy season (December to March) should have more rain than the 

 south, or lee, side. Yet the fact is that there is about the same rain- 

 fall on both coasts at that time. During the southeast monsoon the 

 south (windward) side has a much heavier rainfall than the north 

 (leeward), which is normal. On Celebes, where, according to Woeikof, 

 no such deforestation has taken place, the windward and leeward sides 

 have their normal values of rainfall, the former having a notably larger 

 amount. The case is obviously a very striking one. In reply to a 

 letter from the writer, asking whether newer data from Java tended to 

 strengthen or weaken his previous opinion regarding this case, Dr. 

 Woeikof said : 



I have not modified my views on forests and rainfall. ... It seems to me 

 that in later years at Tjilatjap, on the south coast of Java, which I cited as a 

 station surrounded by forests, the rainfall is smaller than before. This would 

 confirm my views, as in this formerly very little settled part of the island, forests 

 are rapidly disappearing. 



The Java case remains, then, on the authority of one of the best- 

 known meteorologists, a striking example of forest influence on rain- 

 fall. So striking, indeed, is it that one is tempted to ask what other 

 possible controlling factors are here active in producing this sur- 

 prising result. 



Recent European Studies 



The careful observations which have lately been made in Europe by 

 several investigators (Schubert, Hamberg, Schreiber and others) in 

 western Prussia, Posen, Sweden, Saxony, France and elsewhere, have 

 clearly shown that rain-gauges at forest stations, and above the forest 

 crowns, do generally catch somewhat more rainfall than do the gauges 

 at the parallel stations in open country at the same elevations. The 

 excess varies roughly, we may say, between 1 per cent, and at the most 

 10 per cent, of the annual mean. But leading European authorities 

 are pretty well agreed that when definite allowance is made for the 

 effects resulting from differences of exposure, due to the better protec- 

 tion of the forest gauges, the apparent excess within the forest is 

 reduced, by the probability of error, to a very narrow margin indeed. 

 In some cases the margin disappears entirely. Schubert, for example, 

 found a summer excess in forested areas of about 6 per cent. Of these 

 6 per cent., 3 per cent, he believes to be attributable to the better pro- 

 tection of the forest gauge, leaving 3 per cent. And 2 per cent, of these 

 remaining 3 per cent, he thinks still liable to an error. This leaves 

 but 1 per cent. 



Conclusion Regarding Rainfall 



It appears, therefore, that we have as yet no satisfactory or con- 

 clusive evidence that forests, at least in our own latitudes, have a sig- 

 nificant effect upon the amount of rain fall, as distinguished from the 

 amount of the rain catch in the gauge. Nor is there direct and unas- 



