Most people are very much interested in how hot it gets in such
tropics as we traversed. Unfortunately it is very difficult to
tell them. Temperature tables have very little to do with the
matter, for humidity varies greatly. On the Serengetti at lower
reaches of the Guaso Nyero I have seen it above 110 degrees. It
was hot, to be sure, but not exhaustingly so. On the other hand,
at 90 or 95 degrees the low coast belt I have had the sweat run
from me literally in streams; so that a muddy spot formed
wherever I stood still. In the highlands, moreover, the nights
were often extremely cold. I have recorded night temperatures as
low as 40 at 7000 feet of elevation; and noon temperatures as low
65.
Of more importance than the actual or sensible temperature of the
air is the power of the sun's rays. At all times of year this is
practically constant; for the orb merely swings a few degrees
north and south of the equator, and the extreme difference in
time between its risings or settings is not more than twenty minutes.
This power is also practically constant whatever the temperature
of the air and is dangerous even on a cloudy day, when the heat
waves are effectually screened off, but when the actinic rays are
as active as ever. For this reason the protection of helmet and
spine pad should never be omitted, no matter what the condition
of the weather, between nine o'clock and four. A very brief
exposure is likely to prove fatal. It should be added that some
people stand these actinic rays better than others.
Such being the case, mere temperature tables could have little
interest to the general reader. I append a few statistics,
selected from many, and illustrative of the different conditions.
Locality. Elevation 6am noon 8pm Apparent conditions
Coast --- 80 90 76 Very hot and sticky
Isiola River 2900 65 94 84 Hot but not exhausting
Tans River 3350 68 98 79 Hot but not exhausting
Near Meru 5450 62 80 70 Very pleasant
Serengetti Plains 2200 78 106 86 Hot and humid
Narossara River 5450 54 89 69 Very pleasant
Narossara Mts. 7400 42 80 50 Chilly
Narossara Mts. 6450 40 62 52 Cold