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through the kindness and generosity of Dr. Arnold Theiler, C.M.G., 
the Veterinary Bacteriologist to the Transvaal Government at 
Pretoria, and of Dr. Robertson in charge of the laboratory of the 
Medical Officer of Health at Cape Town. Finally, our thanks are due 
to every European in the neighbourhood for the constant courtesy 
they extended, and for the many demands made on their time in 
supplying us with the result of their experiences; to the 
agriculturists who, without exception, placed their animals at oiu- 
disposal for examination; and to the various Government Officials 
who did all in their power to forward the research. 
We established a temporary camp and laboratory near Broken 
Hill, and during our stay there, 36 cases of trypanosomiasis in cattle 
were detected, of which 29 were under continuous observation. This 
work was discontinued on September 30th, in order to prosecute our 
enquiries further North in accordance with the scheme drawn up 
before leaving England. 
The history of many of the 36 cases was uncertain, save that at 
some period within the past six months they had been in a fly district. 
One herd, however, possessed peculiar interest as indicating in the 
most convincing circumstantial manner that biting flies other than 
Glossina can transmit infection. This will be discussed under 
‘ Transmission.’ 
We have already noted that with the opening up of mines, cattle 
previously and primarily intended for agricultural work have been 
utilised for transport, and on primd facie grounds this exposes them 
to greater risks of infection by bringing them into contact with the 
tsetse’s haunts. At the present time one of the four ' roads' from 
Broken Hill must be used for waggon transport. The two which run 
North enter a fly district about fourteen miles out; the third and 
most frequently used one passes through a patch in which tsetse are 
generally seen, about eight miles South, but being a narrow zone, 
night marching may avoid attack. The fourth runs for 112 miles 
South-West to the copper properties there ; only within this last year 
have tsetse been found encroaching at about the looth mile. This 
road joins that coming North from Kalomo, which was used prior to 
the railway. From the neighbourhood of the junction a road runs 
North to the copper mines, and is in fly-belts most of the way, and a 
new one has just been cut in a South-Easterly direction to join the 
