114 
HAROLD’S DISCUSSIONS. 
The ashes borne up into the higher air at the great 
eruption of Coseguina, Central America, were trans¬ 
ported by the upper currents to the northeast, con¬ 
siderably to the east, and fell in noticeable quantities 
on Jamaica, eight hundred miles off. The lower 
current carried them west to the Pacific. 
In 1883, Krakatoa, which is situated in the Strait 
of Sunda, threw large quantities of material high up 
into the air, and the finer particles were carried east 
by the higher currents, as was shown by the showers 
of dust that fell upon the decks of vessels twelve 
hundred miles to the east. 
The peak of Teneriffe, on the Cape Yerde Islands, 
stands isolated in the ocean, and is constantly fanned 
by winds from two different directions. When 
Alexander von Humboldt, the great German natural¬ 
ist and physicist, visited those islands he ascended the 
peak. At the foot, and for some distance up the 
mountainside he found a northeast trade blowing, 
but at the summit a southwest wind almost blew him 
into the crater as he was examining it. Prof. Piazzi 
Smyth spent some time in the observatory located on 
that peak at an elevation of ten thousand feet. His 
records show that there was an almost constant south¬ 
west, and sometimes an almost west wind blowing, 
while the northeast trades continued as regularly at 
the base of the volcano. 
Observations on high mountains in North Amer¬ 
ica, Europe, and Asia show that the upper air to the 
north of the horse latitudes also moves in an easterly 
direction. 
