42 ly. JULY, 1913— JANUARY, 1914 
are even stretches of river where one finds a counter- 
current flowing upstream. And so we creep along, as 
far as possible in the shade of the overhanging trees. 
This canoe has no rudder, but the rower nearest the 
stern guides it in obedience to signals from the one in 
front, who keeps a sharp lookout for shallows, rocks, 
and floating tree trunks. The most unpleasant thing 
on these trips is the way in which the light and heat 
are reflected from the water. One feels as if from the 
shimmering mirror one were being pierced with arrows 
of fire. To quench our thirst we had some magnificent 
pineapples, three for each of us. 
Sunrise brought the tsetse fly, which is active only 
by day, and compared with which the worst mosquito 
is a comparatively harmless creature.* It is about 
half as large again as our ordinary house fly, which it 
resembles in appearance, only its wings, when closed, 
do not lie parallel to each other but overlap like the 
blades of a pair of scissors. To get blood it can pierce 
the thickest cloth, but it is extremely cautious and 
artful, and evades cleverly all blows of the hands. 
The moment it feels that the body on which it has 
settled makes the slightest movement, it flies off and 
hides itself on the side of the boat. Its flight is inaudible 
and a small fly-whisk is the only means of protecting 
oneself to some extent from it. Its habit of caution 
makes it avoid settling on any light-coloured object, 
on which it would be easily detected : hence white 
clothes are the best protection against it. This state- 
ment I found fully confirmed during this trip, for two 
of us wore white, and one yellow clothes. The two of 
* The Glossina palpalis, which conveys the germs of the sleeping 
sickness, belongs, as is well known, to the Tsetse family. 
