TRANSACTIONS OF SECTION E. 315 



would be a slight increase of the rainfall in a country if forests 

 could be grown to occupy a large area previously bare. In 

 France it has been computed that 5 per cent, more rain falls 

 over woodland than in the open ; but one would like to ex- 

 amine this calculation closely and see if here also effect has 

 not been put for cause, and cause for efiect. 



Besides, all kinds of trees are certainly not equally bene- 

 ficial as regards conserving moisture or giving shade or cooling 

 the air. Some plants — sunflower, e.g. — pump water out of the 

 ground enormously ; and the drying capacity of the Eucalyp- 

 tus, as far as the ground around it is concerned, is considered 

 one of its special and peculiar virtues. Even in the case of 

 other trees, the amount of moisture which they draw up from 

 the ground by their sometimes far-reaching spongioles is really 

 enormous. True it is that transpiration and consequent evapo- 

 ration are constantly going on during growth, and sometimes 

 are so copious that an individual tree will perspire its own 

 weight of water in twenty-four hours ; and this undoubtedly 

 does render the air around cooler and moister, though it must 

 be remembered the ground is proportionately robbed of its- 

 moisture. According to some people, trees are as good as 

 artesian wells, and will draw water from heaven as Frank- 

 lin's kite drew electricity from the clouds. They certainly 

 do draw water in large quantities, but it is rather from the 

 earth than from the sky. 



That forests, in a wide sense, operate to materially change 

 the climate of a country, as many have contended, I believe 

 therefore to be a serious mistake, resulting from the confound- 

 ing of cause and effect. The power attributed to trees of 

 drawing rain from heaven is a matter indeed on which many 

 people have held the most extreme views. James Brown, in 

 "The Forester," says, "It is in the power of man to alter, 

 modify, and regulate the climate in which he lives to suit the 

 various kinds of crops he cultivates." One gentleman I know 

 — a well-known litterateur ol s, city in Australia, and the editor 

 of its leading journal — who always entertained the idea that 

 the miraculous virtue of drawing rain lay especially in the 

 Melia azedarach or white cedar. This, therefore, he largely 

 planted in the grounds attached to his house, but it is needless 

 to say that the rainfall over his few acres was not sensibly 

 larger than that of the locality generally. Such notions re- 

 mind one of the old story of King Canute and his courtiers on 

 the sea-shore. Professor Tate, of Adelaide, who liolds views 

 similar to my own, in a lecture delivered by him some years 

 ago w^ent so far as to say that "European experience based 

 on records kept since 1688, and extending up to the present 

 day, failed to prove that the rainfall had decreased as the trees 

 liad been destroyed, and that a similar remark might be ap- 



