COMMERCIAL SICILIAN SUMAC. 



QUANTITY AND VALUE OF IMPORTED SUMAC. 



Sicilian sumac is the best vegetable tanning material known for 

 pale colors and soft tannage, and is consequently extensively used 

 for moroccos, roans, skivers, etc., and for brightening the color of 

 leather tanned with dark materials. An extended investigation a 

 by a committee of the Society of Arts has shown conclusively that 

 sumac-tanned leathers are less likely to be attacked by light and gas 

 fumes, and hence better suited for use in bookbinding than any other 

 known vegetable tannage. 



As good "masculine," or Sicilian mountain sumac, contains from 

 25 to 35 per cent of tannin which is absorbed by hides, it is a very 

 high grade and desirable tanning material, commanding a high price. 

 Consequently it is adulterated to a considerable extent, and much 

 complaint has arisen during the past three or four years both from 

 importers and tanners about the mixing of sumac leaves with stems 

 or other lower-grade and darker-colored substances, an adulteration 

 which not only affects the material itself, but also darkens greatly the 

 leather tanned. In view of these facts it has been deemed advisable 

 to make a careful examination of imported Sicilian sumac. 



Although mineral tanning has largely replaced vegetable tanning 

 in the production of morocco, the importations of foreign sumac have 

 remained about the same for a number of years, as shown by Table I, 

 prepared from statistics issued by the Department of Commerce 

 and Labor. 



TABLE I. Quantity and value of sumac imported into the United States from 1870 to 1907. 



117 



Journal of the Society of Arts, London, 1901, p. 14. 

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