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which to obtain the blood for the protective inoculations). 8. A virulently 
tick-infested paddock—i.e., where susceptible cattle were known to succumb 
to the disease. 4. An acute case of tick fever (from which to obtain 
virulent blood wherewith eventually to test the eflicacy of the protective 
inoculations). 
“These conditions are not, I think, as a rule very difficult of attamment 
in the North. They were all present at Glendower, thirty miles from 
Hughenden, up the Flinders. And here by the kind courtesy of the owner, 
Mr. Robert Gray, and with the hearty co-operation and assistance of Mr. A. W. 
Ferguson, the manager, our experiments were carried out. 
“The required bullocks were brought in for our use from the upper or 
clean end of the run, where neither ticks nor disease had been seen. It was 
proposed to inoculate ten, treat ten with arsenic, and use the remaining ten as 
‘controls.’ 
“On the 24th April ten bullocks were accordingly injected, behind the 
shoulder, with doses varying from one to ten cubie centimetres of defibrinated. 
blood taken from a beast that had completely recovered from a severe attack of 
acute tick fever. Unfortunately two of these bullocks escaped into the bush 
the next day, and all that is known about them is that they were seen alive and 
apparently well some weeks afterwards. ight bullocks, therefore, were 
actually employed in this experiment, and it was decided to use only a corres- 
ponding number of ‘controls.’ As a result of this inoculation most of the 
bullocks developed a certain amount of fever, in some cases reaching as high as 
106-4 Fahr. on the seventh to the fourteenth day. The numbers employed 
were, however, too small to give any very reliable information as to the first object 
of the experiment—namely, to ascertain the amount of immediate danger to 
the cattle as the direct effect of the inoculation. 
“On the same day that these inoculations were carried out, the ten 
bullocks to be treated with arsenic received their first dose. Jor the sake of 
accuracy of dosage and certainty of administration, the arsenic was given in 
weak solution by hypodermic injection. Each animal thus received daily during 
the first week one grain during the second two, and: during a few days of the 
third week three grains of arsenic. > 
“All twenty-six animals subsequently depastured for five weeks on a 
yvirulently infected spot, and became duly .tick-infested. They were tailed by 
day, yarded by night, and their temperature taken each morning at break of 
day. ‘The results of this exposure to virulent tick infection were as follow :— 
7 “Of the ten treated with arsenic, six contracted the fever, and three 
died. 
“ Of the eight ‘controls,’ two contracted the fever; none died. 
“Of the eight moculated, none contracted the fever. 
“On the 29th May—exactly five weeks after the inoculation—all the 
surviving bullocks were subjected to a further test of an injection behind the 
shoulder of 20 c.cm. of virulent blood from an acute case of tick fever. 
“The results of this second test were as follows:— 
“ Of the seven surviving bullocks treated with arsenic (three of which had 
already had the disease from tick infection), two contracted the fever, and 
both died. 
“Of the eight ‘ controls’ (two of which had already had the disease from 
tick infection), four contracted the disease ; none died. 
“ Of the eight inoculated (none of which had suffered from tick infection), 
nore had any rise in temperature whatever. 
“It should be stated that such of the ‘arsenic’ and the ‘control’ bullocks 
as had suffered fever from exposure to the tick infection, were not in any case 
affected by the subsequent injection of virulent blood. Hence as the result of 
both tests it will be seen that— 
“ Of the ten treated with arsenic, 80 per cent. suffered from the fever. 
“Of the eight ‘controls,’ 75 per cent. 
“ And of the inoculated, 0 per cent. 
