TANNING MATERIALS 



65 



The following table, furnished by the Tanners' Council of the United 

 States, shows the approximate quantity of tanning materials consumed 

 annually in this country : 



TANNING MATERIALS CONSUMED CALENDAR YEAR 1918 



1 Figures obtainable for January-May only. Other months probably included in " Not specified." 

 ; Figures cover July- December inclusive only. Other months probably included in " Not Speci- 

 fied." 



3 Figures cover August-December inclusive only. Other months probably included in " Not 

 Specified." 



CHROME TANNING MATERIALS 



Pounds. 



Bichromates 13,344,547 



Other chrome compounds 8,239,942 



PRODUCTION OF HEMLOCK BARK 



Hemlock bark has for a long time constituted the principal source of 

 tanning materials used in this country, and has been commonly employed 

 in tanning leathers ever since the beginning of the industry in America. 

 The nearest competitor was .oak bark, the annual consumption of which, 

 however, has been for many years less than one-half that of hemlock bark. 

 Oak bark has been particularly preferred by some tanners from the 

 earliest days of the industry largely because it has been associated in 



