490 DISEASES OF CATTLE. 



ture, which at first looks streaked and muddy, brightens to a uni- 

 form, thick fluid somewhat resembling molasses. Test it )>y letting 

 about a teaspoonful drip from the paddle into a glass of water (a 

 glass fruit jar or a wide-mouth bottle will do) and stirring thor- 

 oughly with a sliver of wood. It should mix perfectly with the water. 

 Globules of tar which can be seen by looking at the glass from 

 underneath and which can not be l>lended with the water by repeated 

 stirring indicate that more caustic-soda solution is needed. In that 

 case make up more caustic-soda solution of the same strength and 

 add it, not more than a pint at a time, with thorough stirring, until 

 the desired effect is produced. 



If an appropriate glass vessel for making the test is not at hand, 

 take a little of the mixture between the fingers, then dip the fingers 

 under water and try to rub off the tar. It should leave the fingers 

 perfectly clean after a little rubbing with water. If an oily coating 

 remains, more caustic-soda solution is needed. Such an extra addi- 

 tion of caustic soda will be required only in case of a very low-grade 

 chemical or a very highly acid tar. The tar stock should be kept in 

 closed containers, such as a pail with a friction top. 



The quantity of S-B arsenic stock or of tar stock made in one 

 operation can be varied as desired, provided the above-given pro- 

 portions of the ingredients are adhered to. But one should attempt 

 to work the S-B formula on a larger scale only after skill and 

 experience have been acquired. 



The toiled dip is less convenient than the S-B dip, but the final 

 composition and effect of dipping baths prepared from the two are 

 the same. 



To make a 500-gallon bath provide : 



Sal-soda crystals 24 pounds. 



White arsenic 8 pounds. 



Pine tar 1 gallon. 



Put 25 gallons of water into a kettle or tank of from 40 to 50 gal- 

 lons' capacity, heat to boiling, and add the sal soda. When this has 

 dissolved add the white arsenic, then boil and stir for 15 minutes or 

 longer, until the white arsenic has enjtirely disappeared. If in- 

 tended for immediate use cool to 140° F. (by addition of cold water 

 if desired), then pour in the pine tar in a thin stream while con- 

 stantly and vigorously stirring the solution. Immediately empty 

 the liquid into the dipping vat, which has already been three-fourths 

 filled with water, and stir thoroughly. 



All the utensils must be free from greasy or oily matter which 

 would coat the arsenic and hinder its solution. The operation of 

 boiling requires constant attention to avoid loss by foaming. Hard 

 water may be used, but in that case considerable undissolved mate- 



