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