318 REPORT— 1891. 



sumably rainy side is densely wooded, while the leeward side 

 is timberless. Moseley, the naturalist of the "Challenger" 

 expedition, thinks the forests there are owing to heavier rain- 

 fall ; but we have no meteorological statistics from the island, 

 and, as the windward side is the steeper of the two, it may be 

 that the natives, though barbarian, in bygone days have cleared 

 the leeward side for cultivation. The Island of Madeira, as 

 the name implies, was once entirely timber-covered : now, 

 however, through ruthless destruction by Zargo and others, 

 the island is bare except on one side, and that is the wind- 

 ward and rainy. Fire is powerless in a land of incessant 

 rain, or, if it temporarily succeeds, the damage done is speedily 

 repaired. 



It is believed that before human inhabitants became 

 numerous in the world its surface was almost entirely covered 

 with forest. Possibly at that remote period- — and the latest 

 inquiries into the question of the antiquity of man show that 

 it must have been very remote indeed — the mean annual rain- 

 all on the earth was everywhere considerably greater than it 

 is now. Whether that was so or not, in our own day the 

 most extensive natural forests in the world would seem to be 

 generally, though not exclusively, in those parts where the 

 rainfall is known or conjectured to be heavy, if not the 

 heaviest. 



For example, the greatest and most productive forests 

 on earth are in America ; and that Continent, as a whole, 

 has undoubtedly a humid climate. British America has 

 900,000,000 acres of valuable timber. British Columbia and 

 the Washington and Oregon Territories of the United States 

 are densely timbered, and the immense Sequoia {Well hi g ton la) 

 gigantea, is only found where the western slopes of the Nevada 

 Earige intercept the heavy western rains from the Pacific. 

 Passing to South x\merica, we find in the silvas of the western 

 portion of the great plain of the Amazon an area of nearly 

 a million English square miles covered with impenetrable 

 forest and jungle (Brown's "Forester"). In all these lands 

 the rainfall is heavy, in some parts very heavy. Loomis (map, 

 Amer. Jour, of Science, 1882) shades them so as to show 

 a mean annual average of at least 50in., and often over 75in. 

 In Neeah Bay, Washington Territory, the amount is ]23in. ; 

 in Blockhouse, Oregon, 96in. ; in Halifax, N.S., o4in.; in 

 New Westminster, 58in. What it is in the forests of Brazil, 

 particularly in the uplands towards the Andes, I cannot dis- 

 cover, but it must be very large, for, the latitude being tropical, 

 the trade - wind striking against the eastern flanks of the 

 mountams must cause immense precipitation. The Andes are 

 clothed with forest along their entire length either on one side 

 or both sides, because the mountains catch the eastern rains 



