14 THE ALLEGED DESICCATION OF EAST AFRICA 
of Kenya and obtain a rough estimate of its original altitude ; 
the extra area of the ice-fields under these conditions would 
doubtless partially account for the traces of glaciation at a 
lower level. 
Dr. Rocatti, the geologist to the Abruzzi expedition, 
observed traces of glacial action on that mountain on the east 
side, at 4870 feet above sea-level ; the lowest level of the 
existing ice is now about 18,680 feet, an astounding recession 
of 8780 feet. The climate at the time this vast area of snow- 
field existed on mountains like Kenya and Ruwenzori must 
have been extraordinarily unlike present-day conditions. 
The botanical evidence available, however, shows that a 
more or less common alpine flora is to be found on all the high 
mountains from Abyssinia to Kilimanjaro, and this flora is 
quite unlike anything to be found in the intervening country. 
This fact tends to show that at one time, and, speaking 
geologically, at a not very distant period, there was a con- 
tinuous connection of land at a high level between these points 
so remote. Gregory estimates that at that time the mean 
temperature must have been at least 17° lower than at present. 
Now the prevailing wdnds on the coast are the north-east and 
south-west monsoons, which blow periodically parallel to the 
coast in one direction or the other according to the seasons. 
Up country, at an elevation of a few thousand feet, the changes 
in the monsoon are not felt, but over the bulk of the year a 
strong wind, generally easterly and a little south of east, blows 
during the greater part of the day, and it is believed that these 
are the trade winds blowing high over the monsoon winds which 
keep near coast-level. It is very marked on the big mountains 
in the interior, such as Kenya, Kilimanjaro, and Elgon ; in 
the early morning they are generally quite clear, but about 
10 a.m. the clouds sweep up from the south-south-east and 
collect on the mountains and blot them out from view for the 
rest of the day. These are believed to be clouds borne inland 
by the trade winds, and the moisture they carry is precipitated 
mainly on the south and south-east slopes ; the proof of this 
precipitation exists in the much greater growth of forest on the 
south and south-east sides of the mountains referred to. Now, 
when there w T as a continuous ridge of high land between 
