Page:The National Geographic Magazine Vol 16 1905.djvu/553

Rh moderate temperature and charged with much moisture.

The result is that in the latitude of Yorkshire every mountain mass over 3,000 feet high is covered with eternal snow and sends glaciers down to the sea.

I was convinced by what was going on under my eyes that it only required an upheaval of the land of 2,000 feet or so to cover the whole of Patagonia with ice. But then the climate would still not be very severe. The temperature of the wind from the sea would be the same, and such part of it as blew along the channels and on the lower land would moderate the cold caused by the ice-covered slopes.

The shores of the whole of western southern Patagonia, deeply indented with long and deep fiords, indicate, ac- cording to all received views of the origin of such formations, that the land was formerly higher, while signs of glaciation are everywhere present.

The results of geographical research show us that in many parts of the world climate must have greatly changed in comparatively recent times. In the now arid regions of northern Africa, central North America, and in parts of Asia, there is ample evidence that the climate was in times past more humid. In a remarkable paper on the causes of changes of climate, contributed by Mr F. W. Harmer to the Geological Society in 1901, and which has not ob- tained the notice it deserves, it is pointed out how changes in the distribution of the prevalent winds would vastly alter climatic conditions. Like everything else in nature, and especially in the de- partment of meteorology, these ques- tions are exceedingly complex, and similar results may be brought about in different ways ; but there can be no doubt that the climate of South Africa would be greatly modified, and more rainfall would occur, if only the cyclonic storms which now chase each other to the east- ward in the ocean south of the Cape of Good Hope could be prevailed upon to pursue a slightly more northerly line, and many obstacles to the agricultural prospects of South Africa now existing would be removed. This is, howevf beyond the powers of man to effect ; but, as I have just said, there are other ways of attaining the object, and it is earnestly to be hoped that the attention now being paid to afforestation may re- sult in vigorous efforts to bring about by this means the improvement in hu- midity so much required in many parts of the country.

The other recent event in geograph- ical exploration is the result of the expedition to Lhasa. It was an un- expected solution of this long-desired knowledge that it should come from political necessities and by means of a government mission. The many ardent travelers who have dreamed of one day making their way in by stealth have thus been disappointed, but our knowl- edge is now fuller than could otherwise have been gathered.

The most important fact is the reve- lation of the fertility of a large part of southern Tibet. Much has been added to topographical knowledge, but the route maps of the secret Indian native surveyors already had given us a rough knowledge of the country on the road to Lhasa. It was not, however, real- ized how great was the difference be- tween the aridity of the vast regions of the north, known to us from the travels of men of various nationalities, and the better- watered area in the south, though from the great height of the plateau — some 12,000 feet — the climate is very severe. The upper course of the Brah- maputra has been traced by Captain Ryder, but unfortunately a political veto was placed on the project to solve the interesting problem of how this great