TABLE II.-Chemical and microscopical examination of Sicilian sumac sampled in 1905—Continued.

8. 53 1.38 54.9 50.0
25 per cent len- 7.69 8. 91 1. 62 49. 4 44.8
tiscus, venti-

lated.

per cent pure,

extra ventilated.

345

E. & A. Graziano,
Palermo.

O. S. Janney & Co.,
Boston.

do

May 12,1905

100 7.97 7.67 1.56 58. 6 53.8 4.8 18.9 34.9 1.7 6.8 Sumac only.

Guaranteed pure, 8. 12 8.09 1.34 57.9 51.2 6.719.731.5 2.810.0 extra ventilated.

Warranted pure, 7.86 8. 83 1. 53 54. 8 49. 4, 5. 4 20. 0 29.4 3.011.8

Strong and pure, 7.61 9. 561. 83 52. 7 47.4 5.3 17. 4 30.0 2.0 8.0 Sumac only. extra ventilated.

Warranted 100 8. 14, 7. 87 1. 70 57. 452. 9, 4. 518. 4 34.5 3.5 10. 0

Warranted pure, 7.38 7. 41 1. 34 50. 9 45.6 5.3 20.0 25.6 2.2 7.1 Lentiscus abunventilated.

dant, possibly some tamarix.

Guaranteed pure, 8.20 7.88 1. 51 56. 5 52. 3.9 18.7 33.9 1.3 4.7 Sumac only. extra ventilated.

.do

INVESTIGATION OF 1905.

July 12, 1905

25 per cent lentis- 7.93
cus, warranted
pure sumac.

Do.

7.561.16 55. 851.2 9.04 1. 60 53. 148. 2

4.617. 433.8 4.918. 329.9

.do.

100 per cent guar- 8.20 7.761. 28 58. 453.3 5.119.034.3 1.4 6.7 Sumac only. anteed pure, ex

TABLE II.-Chemical and microscopical examination of Sicilian sumac sampled in 1905-Continued.

INVESTIGATION OF 1907.

During 1905 and 1906 there was so much agitation of the question of sumac adulteration in the leather trade journals, and buyers had to become so well informed on the question, that it was thought advisable again to collect and examine samples. This was done in the spring of 1907, exactly as before, the samples being secured from all incoming consignments for a time before they passed into the hands of the consignee. The results of the examination of these samples are given in Table III, page 22.

DISCUSSION OF ANALYTICAL DATA.

Seventy-five per cent of the 53 samples examined were pure sumac or contained but traces of other material such as may have been present accidentally. The pure samples contained from 25.6 to 35.7 per cent and averaged 30.6 per cent of tannin, or 1.3 per cent lower than the 1905 samples. Microscopical examination showed that 25 per cent of the samples examined were adulterated with lentiscus, while one sample was pure lentiscus and another was Turkish sumac. The adulterated samples contained from 22.4 to 30.4 per cent and averaged 26.3 per cent of tannin or 0.3 per cent lower than the 1905 samples. These facts indicate that while adulteration is not so generally practiced as in 1905, individual shipments are apparently adulterated to about the same extent.

The lowest tannin content of all the samples was 22.4 per cent, the highest 35.7 per cent, and the average 29.4 per cent, the latter figure being practically identical with the average tannin content of the 1905 samples. Color tests were made on but few extracts, which indicated a somewhat higher average color in the pure 1907 samples than in the pure 1905 samples. Only 3 of the 13 samples which were found to be adulterated were labeled to that effect. The other samples were either labeled pure sumac or marked so as to give the impression that they were pure Sicilian sumac.

These results indicate that from 1905 to 1907 there was a decrease of about 16 per cent in the importation of adulterated shipments of sumac, but that those shipments which were sophisticated had been adulterated with practically the same percentage of lentiscus as formerly. The practice of labeling adulterated shipments "pure sumac" or "warranted 100 per cent pure sumac" appears to be as general as formerly, so that it is still absolutely necessary for a buyer who would be sure that he is purchasing a pure, high-grade sumac to have it examined.

117