( 68 ) 



also have no direct influence upon the cosmical temperature of a locality, but this cannot he said 

 with reference to the amount of moisture. In India the evergreen forests are the true condensers 

 of moisture as they deposit the moisture in the soil, which nourishes the springs and creates an 

 equable drainage in the plains. The destruction of such forests regularly diminishes the amount 

 of water-drainage and the consequences are at once apparent evaporation in the plains dimi- 

 nishes and the hot dry season is rendered more excessive. A dry hot season, however, is for 

 India as injurious to the growth of vegetation, as a severe winter is in temperate regions, and 

 it is this period of the year, which (along with the impermeability of substrata) prevents the 

 extension of evergreen tropical forests over large tracts, and restricts them to sheltered and 

 well-watered vallies in the hills. Our aim, therefore, should be to equalize the amount of 

 moisture as much as possible, for though the atmosphere may be greatly heated, if it is suffi- 

 ciently saturated it will promote tropical vegetation. 



Wanton destruction of forests has told its lesson everywhere between the tropics, while 

 examples of the beneficial influence of forests are not wanting. When the Romans subjugated 

 Spain it was a fertile country, the Southern provinces of which, especially, were covered with 

 forests ; now it is an arid country, devoid of forests. Ali Pasha burnt down the forests of the 

 Peloponnesus, and the consequence was drought and famine. The Russian General Dibitsch 

 Balkansky destroyed the forests of the Caucasus for the purpose of routing and starving the brave 

 Circassians and completely succeeded in his inhuman design. Mauritius, the Azores, Jamaica 

 and other West Indian islands, and even North America, have all had their lessons in this respect. 

 On the other hand we learn, that the planting of 20 square miles of trees in Egypt has in- 

 creased the number of rainy days to 40 ; the planting of thousands of acres with trees, chiefly 

 Acacia mollissima and lophanta, Eucalyptus, etc., in Algiers, as also the restoration of forests on 

 St. Helena and Mauritius, have doubled the amount of dew and rain. The Departments des 

 I-andes in France (along the Bay of Biscay), where malarious fevers prevailed, have now 

 become healthy districts under Napoleon III, who caused upwards of 16 German square 

 miles of swampy lands to be planted with trees (chiefly Piniis mantima). 



The French and German Forest literature furnish additional material in support of the 

 importance of forests in nature's household, and E. Ebermeyer's work on the Physical influence 

 of the forests upon air and soil etc. treats the question more fully and scientifically. 



It can, therefore, be no more a question, whether forests influence the climate of a country, 

 but the questions in future should rather be : How can we best prevent the destruction of forests ? 

 How can we raise forests in arid districts ; of what kind should they be and, where should they 

 first of all be raised ? The Government, however, can hardly be expected to take upon itself 

 this heavy duty single-handed and the co-operation of the inhabitants is therefore indis- 

 pensable. A Forest Officer who succeeded in replanting large tracts of land with forests, 

 and who by doing so shewed a large financial deficit, would hardly be thanked for a measure 

 which yielded no present returns, for the public is often slow to recognize the good intentions 

 of the originator of such schemes. Yet the beneficial results of the measure would undoubt- 

 edly be felt in after years when the Agricultural population reaped the fruits of a country 

 rendered fertile by the existence of forests whose beneficial influence would avert or mitigate 

 the horrors of famine. Laws exist in several countries which render the planting of trees by 

 the people compulsory, but I need only mention two examples here, viz., that in Japan every 

 one who cuts down a tree is required to plant another in its stead ; and in Biscay (France) 

 every land proprietor who fells a tree is required to plant two in its stead. In some coun- 

 tries like Java, it is a custom with the natives to plaut a fruit tree on the occasion of the 

 birth of a child, and this tree is carefully looked after as being the only record of the age of 

 the child. Dr. Schomburgk in his interesting lecture on the influence of forests on climate 

 (of which I have made fre6 use) tells us an anecdote which well deserves a place here, as 

 it may influence the native mind : When Ulysses, after a ten years' absence, returned 

 from Troy, he found his aged father in the field planting trees. He asked him, why, being 

 now so far advanced in years, he put himself to the fatigue and labour of planting what he was 

 never likely to enjoy the fruits of? The good old man, taking his son for a stranger, 

 replied, " I plant for my son, Ulysses, when he comes home." 



rather increased within the last 100 years in spite of the enormous extirpation of forests. The amount of rainfall at 

 Viviers in Southern France has increased in the period between 1777-1818 from 31 to 37 inches, although the forests 

 in the environs have been almost totally destroyed. The wooded plains of Germany have not only an equal but a 

 rather lesser annual rainfall than woodless Holland. The forests only act upon the distribution of the annual rainfall 

 and as reservo;.rB for moisture, and as such they are certainlj' of high importance. The amount of rainfall in 

 Europe is produced not so much by local evaporation as bj' passing currents of air laden with moisture, but matters 

 are altogether different between the tropics, where the amount of moistuie directly depends upon local evapoi-ation ; 

 the destruction of forests must, therefore, conspicuously effect the diminution of rainfall, for forests serve a two- 

 fold purpose here on the one hand a powerful evaporation is produced from the surfaces of the leaves of trees, 

 while on the other the coolness that reigns in the forests causes the precipitation of atmospheric moisture. So far 

 Kabsch (Das Pflanzenleben der Erde 1870, p. 125). 



