Cattle-Fever Ticks. 



21 



Table S. — Date on which seed ticks will appear after ticlcy cattle have been 



placed on tick-free land. 



BASED ON DATA OBTAINED AT BATON EOUGE, LA., AUBURN, ALA., AND DALLAS, TEX. 



Date cattle placed on tick-free 

 pastures. 



Jan. 1 to Feb. 4, inclusive. 



Mar.3 



Apr. 15 



May 1 



Jmio 5 



July 1 



Aug. 5 



Sept.l 



Oct. 1 



Nov. 1 to Dec. 15, inclusive. 



BASED ON DATA OBTAINED AT KNOXVILLE, TENN. 



Jan. 11 to Mar. 4, inclusive. 



Apr. 1 



May 15 



June 12 



July 3 



Aug. 6 



Sept. 4 



Oct. 2 



ARSENICAL DIPS. 



PROPERTIES OF SUBSTANCES USED IN MAKING ARSENICAL DIPS. 



The successful preparation of an arsenical dip calls for some 

 knowledge of the properties of the raw materials. 



WHITE ARSENIC. 



White arsenic [arsenic trioxid^ arsenious or arsenous oxid or acid) 

 must be purchased in the form of a fine powder and under a guaranty 

 of 98 or 90 per cent purity. Water, even when boilino;, dissolves it 

 only slowly, but by the use of certain other chemicals it may readily 

 and abundantly be brought into solution. 



One must never forget that wdiite arsenic is a violent poison to 

 man and animals. So are the concentrated dips prepared from it. 

 The precautions necessary for safety will be discussed under a 

 separate section, and any person who has anything whatever to do 

 with arsenical dips is advised to read it often enough to keep the 

 points fresh in mind. 



CAUSTIC SODA. 



Caustic soda [sodiunh Kydroxid) , on account of its wide range of 

 application by chemists, pharmacists, and manufacturing industries, 

 occurs commercially in a number of different forms, as powder, 

 sticks, solid masses, or broken fragments; in color it ranges from 

 pure white to grayish or brownish tints. For the use of chemists and 

 pharmacists it is put up in glass bottles; for industrial purposes it 

 is supplied in various-sized cans or drums of thin sheet iron. The 

 latter is the variety that should be purchased for making dip. The 



