€6 FOREST DESTRUCTION IN NEW SOUTH WALES. 



predict the seasons for even more than a year, and would certainly 

 t>e a valuable addition to the science of meteorology. The opinion 

 which is prevalent in many parts of this Colony, that a droughty 

 year in Europe will be followed here by a droughty year within a 

 given time, seems to indicate a glimmering consciousness of some 

 such connection as I have endeavoured to trace out. 



In conclusion, I will say that for many years I have endeavoured 

 to find upon what evidence rests the popular opinion that forest 

 destruction reduces the rainfall of any country and dries up 

 springs. I have seen many cases quoted where the occurrence of 

 a severe drought was shown to be coincident with the destruction 

 of forest in some particular place, but that would not prove 

 anything, unless it could also be shown that droughts did not 

 occur before the forests were destroyed, and would not have 

 occurred if the forest had not been destroyed, and this part of the 

 proof is always wanting. That large forest growths have been 

 destroyed in many places without reducing the rainfall or the 

 flow of water in the streams we have the most undeniable proof, but 

 I do not think there is a single case recorded in the whole World 

 where an accurately kept record of rainfall and flow of water in 

 streams, or of either, shows a permanent diminution coincident in 

 time and corresponding in degree with the gradual diminution of 

 forests. That there is a connection between rainfall and forest 

 growth there can be no doubt, nor can we doubt that they stand 

 to each other in the relation of cause and effect, but the popular 

 belief has reversed the order of this relation, holding the forest 

 to be the cause of rainfall when it is in reality one of the effects 

 of rainfall. From the well known power of the eucalyptus tribe 

 to dry up sw^ampy places, which has been made use of both in 

 Europe and America, we might expect that the result of forest 

 destruction where the trees were of this order would be much 

 more decided and more quickly apparent, than where the trees 

 were of a different kind like those of Europe or America, but the 

 difference is, I think, only a difference in degree not in kind. In 

 both cases the life of the tree is maintained in the same way, and 

 we ought to find that forest destruction in Europe or America 

 produced results similar in character to those produced in 

 Australia, though perhaps they might differ in degree. For these 

 reasons, I think, it is now time that those teachers of science 

 in Europe and America, who hold by and teach the popular theory 

 that forests do cause increased rainfall and an increased flow of 

 water in springs and water-courses, and that deforestation does 

 reduce the rainfall and flow of water in springs and water-courses, 

 should reconsider their theory and the evidence on which it rests. 

 This seems to me very necessary in the light of the experience 

 gained in Australia, where forests are destroyed wholesale for 

 pastoral purposes. 



