SOME FOREST SECRETS 



trees are evenly graded and occupy equal areas and the 

 forest may return its full annual interest on the timber- 

 producing capital." 



The part taken by the Colonial Governments in the 

 preservation of the Forests consists mainly in the ad- 

 ministration by the Forestry Departments of large For- 

 est reserves, in which no timber can be cut without a 

 government permit. To illustrate the multiplicity of 

 the ways in which the forests affect the prosperity of 

 the country, I mention seven of the purposes which the 

 forest reserves are intended to achieve, namely, to sup- 

 ply forest produce continually for local use (railways, 

 buildings and native requirements) and for export and 

 to add to revenue; to conserve the water supply and 

 control the "run-oflf" from the hills, thus regulating 

 waterfalls for power, maintaining irrigation and the 

 flow of springs, ensuring a higher level in the rivers in 

 the dry season and preventing floods which deposit large 

 quantities of barren soil in the valleys and ruin them for 

 agriculture; to increase the humidity of the atmosphere, 

 and so promote the growth of crops. Experiments here 

 and abroad prove that forests increase rainfall by 

 twenty-eight per cent; preventing land slides and ero- 

 sion, silting of rivers and shifting sands; they also act 

 as barriers against the spread of insect and fungoid pests 

 from one cultivated area to another; they conserve and 

 improve the qualities of the soil, until required for cul- 

 tivation by the increase of the population while provid- 

 ing a sanctuary for game and grazing in time of famine. 



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