20 NATURAL HISTORY OF SLEEPING SICKNESS 



Thus Gordon Gumming in 1850 wrote as follows :i 

 " When under the mountains on the south bank of the 

 Limpopo river I met with this famous fly whose bite is 

 certain death to oxen and horses. This fly is similar to 

 the fly in Scotland called ' Kleg,' but a little smaller. 

 They are very quick and active, and storm a horse like 

 a swarm of bees, alighting on him in hundreds and 

 drinking his blood. The animal thus bitten pines away 

 and dies at periods varying from a week to three months." 



And again : " The next day one of my steeds died of 

 Tse-tse. He had been bitten under the mountain range 

 lying to the south of this fountain. The head and body 

 of the poor animal swelled up in a most distressing 

 manner before he died. His eyes were so swollen that 

 he could not see, and in darkness he neighed for his com- 

 rades who stood feeding beside him." 



Again, Livingstone in 1857 wrote as follows : ^ " The 

 peculiar buzz when once heard can never be forgotten 

 by the traveller, for it is well known that the bite of 

 this poisonous insect is certain death to ox, horse or dog. 

 In this journey we lost forty-three oxen by its bite. 

 We watched the animals carefully, and believe that not 

 a score of flies were ever upon them. 



" A most remarkable feature is the perfect harmlessness 

 of the bite to man and wild animals." The italics are 

 mine, to emphasize that the scientific mind of the great 

 explorer had noticed this pregnant fact, although the full 

 significance was not made plain until Bruce's work was 

 published. ** We never experienced the slightest injury 

 from them ourselves, although we lived two months in 

 their habitat, which was in this case as sharply defined 

 as in many others ; for the south bank of the river was 

 infested by them, and the north bank, where our cattle 



^ Five Years of a Huntefa Life in the Far Interior oj South Africa, 

 vol. ii. p. 210, etc. 



* Missionary Travels and Researches in South Africa, p. 79, etc. 



