HIPPOPOTAMUS 203 



It is of course conceivable that the river itself auto- 

 matically brings down food sufficient to supply a certain 

 percentage of its pachydermatous population. Thus 

 there is the little water-cabbage (Pistia stratiotes] which 

 drifts down in millions from the Sudd regions. One sees 

 acres of backwaters and by-channels blocked solid with its 

 accumulations, and these stores would yield food for many 

 hippos. No more obstructive agent to navigation exists 

 than this water-cabbage it is largely to its malevolence 

 that we owe the Sudd! hence, should this hypothesis 

 be correct, the antediluvian amphibian is to-day helping 

 (albeit unconsciously) to advance modern progress. 



It is notable that even when totally unharassed, the 

 hippopotamus deliberately selects the darkness of night 

 as his period of activity and all day lies up somnolent. 



By nature, no animal is more inoffensive in disposition ; 

 yet persecution modifies that mildness, and to-day many 

 hippos have developed characters both savage and 

 truculent. Moreover, their vast strength and armoured 

 jaws give the power to enforce that truculence. On 

 Upper Nile it is of daily occurrence that the dug-out 

 canoes of the natives are attacked and scrunched into 

 matchwood, some or all of the crew inevitably perishing 

 in the mle. Although never myself having experienced 

 an actual attack, yet twice when "probing" for a dead 

 hippo (with the view of making fast a rope to his leg 

 and so towing him ashore before dark) the demeanour 

 of the rest of the herd became so obviously menacing, 

 bellowing and blowing half round our boat, that I 

 promptly gave the order to "pull away" and felt no 

 small relief when we had regained shallow water. 



A curious metaphysical fact relative to the hippo- 

 potamus deserves note that is, that when the animal 

 itself is deep under water, yet its snorts and gruntings 

 may still be distinctfy audible, albeit no air-bubbles or 

 other trace appears on the surface. I first noticed this 

 phenomenon in East Africa and mentioned it in On 



