EXTERMINATING THE TEXAS-FEVER TICK. 23 
If a stronger arsenical dip is desired, 10 pounds of arsenic may be 
used in place of 8 pounds, but in general the stronger solution should 
not be used. In warm weather particularly it is not advisable to use 
a solution stronger than that given in the above formula, if the 
animals are to be treated every two weeks. 
In preparing the dip, a large caldron or galvanized tank is required 
for heating the water in which to dissolve the chemicals. Thirty or 
forty gallons of water should be placed in the caldron or tank and 
brought to a boil. The sodium carbonate is then added and dis- 
solved by stirring. When this is accomplished, the arsenic is added 
and dissolved in a similar manner. ‘The fire is then drawn and the 
pine tar added slowly in a thin stream and thoroughly mixed with the 
dip by constant stirrmg. This strong stock solution is diluted to 500 
gallons before using. 
If one desires, double or triple the amount of stock solution indi- 
cated above may be prepared at one time, provided a large enough 
vessel is available. In case a small vessel holding 20 to 25 gallons 
must be used, half of the stock solution indicated may be prepared. 
This will, however, consume so much more time in preparing large 
quantities that when possible it is advisable to provide a large vessel 
for dissolving the chemicals. 
The stock solution, if it is to be used for dipping, may be placed in 
the vat as fast as it is prepared, or, if it is to be used for spraying, may 
be stored in barrels. The most convenient way of diluting the dip is 
to run the water into the vat through a hose or pipe. The capacity 
of the vat, if not known, should be calculated, and for convenience 
the water line marked at several places on the sides. After the exact 
amount of stock solution necessary to furnish diluted dip to fill the 
vat has been prepared and placed in the vat, all that is necessary is 
to allow water to flow into the vat until the surface of the dip reaches 
the marks made on the sides of the vat. For example, if the capacity 
of the vat is 2,000 gallons, then four times the amount of the stock 
solution necessary to make 500 gallons of the dip should be prepared, 
placed in the vat, and the latter filled with water to the 2,000-gallon 
mark. 
When for any reason it is not convenient to follow the above method 
of diluting the dip, a stock solution may be prepared in which the 
quantity of ingredients for 500 gallons of diluted dip are dissolved in 
50 gallons of water. Nine parts of water to one part of this stock 
solution will then give the proper dilution. This stock solution is 
found very convenient when small amounts of diluted dip are required 
from time to time for spraying cattle. Fifty gallons of the stock 
solution can be placed in a barrel and just the amount required each 
time taken out and diluted. 
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