W. F. Cooper and H. E. Laws 
213 
It would have been interesting to see the results, had these tests 
been extended. For instance, it is exceedingly probable that in Lot C, 
two animals of which, out of a total of five, failed to exhibit any febrile 
symptoms within the period of the experiment (eighteen days), the 
incubation could have been prevented entirely by continuing the dipping 
at five-day intervals. In Lot C again, the earliest appearance of fever 
was on the fifteenth day after dipping and it is quite within the bounds 
of probability that, up to as much as fourteen days, the animal was 
non-infective and could have been used for transport purposes within 
that period with perfect safety. It is very desirable to establish this 
point in order that some system of allowing transport, under licence, 
to and from infected areas might be devised. Such a system would 
prove a great boon to farmers and graziers in certain parts of South 
Africa and particularly in British East Africa. 
Appendix VIII. 
Dipping Experiments at Elliotdale. 
East Coast Fever broke out at Elliotdale (Lat. 32° S., Long. 29° E.), 
in the Transkeian Native Territories, South Africa, in February, 1910, 
as diagnosed by Veterinary Surgeon J. Spreull. 
By that time, the chief deductions expounded in the body of this 
paper had been made and this outbreak appeared to offer an excellent 
opportunity of putting them to an extensive practical test. As it 
was necessary to get the work under way without delay, it was impos¬ 
sible to make elaborate preparations, and, after all, our object was to 
ascertain whether, by means of dipping, animals could be rendered 
immune to the disease. 
On May 18th, 1910, one of us (H. E. L.) commenced operations with 
500 head of Kaffir stock (bullocks, cows and calves—mixed) collected 
in the district. A dip, prepared by us at Gonubie Park, consisting of 
sodium arsenite with an emulsion, was used. At that time there were 
no cattle swim baths in the area and we had to rely on the spraying 
method, using the Seabury machine 1 . The spraying operations were 
started at the end of May and were repeated at intervals of five days. 
Between the first and second sprayings one animal died, and after 
the second dipping another animal died, but from that time no further 
deaths occurred amongst the sprayed stock. 
1 The construction and mode of operation of the Seabury machine is dealt with in 
Lounsbury, C. P. (1908) and Cooper, W. F. and Laws, H. E. (1908). 
Parasitology vttt 
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