294, QUEENSLAND AGRICULTURAL JOURNAT. {1 Man., 1899. 
TEXAS FEVER PROBLEMS.—II. 
In the preceding article on this subject it was shown that Texas fever is 
transmitted from the southern to the northern animal by means of the cattle 
tick, and it is assumed, for all practical purposes, that this is the only way in which 
the contagion is disseminated under natural conditions. The disease may be 
produced Ly the investigator through the inoculation of blood, or in very 
exceptional cases a similar inoculation may be made by flies or other biting 
insects. That there is practically no danger of the contagion being eavried by 
anything other than the tick is shown by the well-known fact that hundreds of 
thousands of southern cattle are taken north for grazing every winter without 
causing disease, although the micro-organism of ‘exas fever remains in their 
blood in a virulent condition during their whole lifetime. If flies or other 
insects were a frequent factor in transmitting the contagion, we should hear of 
numerous outbreaks of Taxes fever wherever cattle from the infected district 
are grazed upon the same ranges with susceptible natives. The absence of 
such outbreaks when ticks are not carried is the best possible evidence that 
they alone need be feared. 
In the report on Texas fever prepared under the writer’s direction and 
published in 1898, it was clearly stated that the results of the investigations 
therein made public bring up the very important question whether southern 
cattle “cannot by some means be freed from ticks so that their transportation 
may go on without any restriction during the entire year.’ Several methods | 
for accomplishing this were suggested. It was stated that “ cattle might be 
subjected to disinfecting washes of various kinds, or else they might be run 
through disinfecting baths which expose the whole body to the action of the 
liquid used.” 
Other methods, frequently discussed in conversation but which were not 
mentioned in the report, are the application of the tick-killing liquids with 
brushes or mops or with a spraying apparatus. These last-mentioned methods 
were discarded as too slow and inefficient. However, spraying is used con- 
siderably in South Africa, and mops and brushes are often found convenient in 
this country when but a small number of animals is to be treated. The plan 
of submerging the animals in a dipping-vat filled with the selected liquid is, 
however, unquestionably the only safe and satisfactory method for treating 
animals that are to be shipped for grazing purposes. Substances sprayed or 
rubbed upon the animals are not so irritating in their effects as when used in 
the vat, but it is nearly or quite impossible to reach all of the ticks in the folds 
of the skin, and particularly between the legs. ‘Che conclusion was therefore 
reached that dipping is the only practical method of destroying the tick. 
Having decided that the ticks must be killed by dipping the cattle, the 
next question to be solved was the composition of the liquid which should be 
used. This mmor problem, which at first sight appears very simple, has really 
giyen as much trouble as any other question connected with the disease. The 
ticks were first experimented with in the laboratory, and it was found that the 
ordinary insecticides, poisons, and mineral acids even had little effect upon 
them. They had a greater power to resist such substances than was possessed 
by the cattle. For a long time the prospects of finding a tolerably efficient 
ip were very discouraging. ; 
The first person to build a vat and to dip cattle appears to have been Mr. 
R. J. Kleberg, of Santa Gertrude’s Ranch, Texas. His cattle were dipped ina 
strong solution of carbolic acid as treatment for mange, and he observed that 
many of the ticks dropped off or died soon after the dipping. As the results 
of the investigations of the tick as the carrier of the Texas fever infection were 
fresh in Mr. Kleberg’s mind, he informed the department of his observation 
and placed his dipping-vat and his “tieky” cattle at the disposal of the 
Bureau of Animal Industry for further experimentation. An inspector (Dr. 
Norgaard) was stationed there, who gave his whole time to this question and 
tested a vast number of different mixtures. Some of these dipping solutions 
killed a portion of the ticks and caused severe inflammation of the skin of the 
