16 FARMERS* BULLETIN 909. 



injury. However, when it is handled and used with proper care it 

 is a safe and efficacious remedy. The arsenic, as well as the other in- 

 gredients, should be weighed carefully. While the arsenical solu- 

 tion is being prepared care should be taken not to inhale the powder 

 or the vapor given off, and the operator should stand on the wind- 

 ward side of the kettle as far away as possible. Care should be taken 

 not to expose, more than necessary, the hands or other parts of the 

 body to the action of the dip. The hands should be washed fre- 

 quently and care taken not to get the clothing wet with the dip. 



If animals are allowed to drain where pools of dip collect from 

 which they may drink, or if they are turned into feed lots or pastures 

 while the dip is dripping from their bodies so that the feed may 

 become soiled, losses are liable to occur. 



The arsenical dip left in the vat may be used again if it is not 

 filthy. When not in use the vat should be covered or inclosed by a 

 fence so that animals may not have access to it. In- cleaning the 

 vat the contents should not be emptied or allowed to flow into 

 streams or on land or vegetation to which animals have access. The 

 best plan is to run the dip into a pit or trench constructed for that 

 purpose and protected by fences. The trench should be located so 

 the dip will not be carried by seepage into the water supply of the 

 farm or the neighborhood. 



Although the arsenical dip is commonly used cold, it should not 

 be cold enough to chill the animals. The temperature should range 

 between 65 and 90 F. 



COAL-TAR CREOSOTE DIPS. 



The coal-tar creosote dips are sold under many trade names. They 

 are made from coal-tar derivatives and the principal ingredient is 

 creosote oil, which is made soluble in or miscible with water by 

 means of soap. When diluted with soft water they are efficacious in 

 eradicating cattle lice. Before using them with hard or alkaline 

 water the test described on page 14 should be made. There is no 

 field test for determining the deterioration of these dips, conse- 

 quently in replenishing the dip the percentage of active ingredients 

 in the vat is largely a matter of guesswork. Coal-tar creosote dips 

 may be used cold or warm, but the temperature of the bath should 

 not exceed 95 F. 



These dips should contain, when diluted ready for use, not less 

 than 1 per cent by weight of coal-tar oils and cresylic acid. In no 

 case should the diluted dip contain more than four-tenths of 1 per 

 cent nor less than one-tenth ot 1 per cent of cresylic acid ; but when 

 the proportion of cresylic acid falls below two-tenths of 1 per cent 

 the coal-tar oils should be increased sufficiently to bring the total of 



