Two skins, both dressed by the "Schrot-beize," a Persian lamb and an astrachan, after dyeing had shrinking points almost 10 degrees higher than when undyed. The extra tannage which the skins received from the tannins used in the dye mixtures for these furs, accounts for this increased resistance to heat.
The following tables give the observed figures in the different experiments:
TABLE I +-------------------+------+------+------+ | | A | B | C | | | S.P. | S.P. | S.P. | +-------------------+------+------+------+ |_Salt-acid Tan_ | C. | C. | C. | |Australian Opossum | 46° | 58° | 45° | |Marmot | 45° | 50° | 42° | |Skunk | 47° | 56° | 43° | | | | | | |_Chamois Tan_ | | | | |Mink | 52° | 61° | 45° | |Muskrat | 50° | 58° | 42° | +-------------------+------+------+------+ A--Water B--Water plus 1% Ammonia (s.g. 0.910) C--Water plus 1% Sulphuric acid (66° Beaumé)
TABLE II +-------------------+------+------+------+ | | A | B | C | | | S.P. | S.P. | S.P. | +-------------------+------+------+------+ |_Salt-acid Tan_ | C. | C. | C. | |Australian Opossum | 53° | 52° | 54° | | | | | | |_Chamois Tan_ | | | | |Mink | 59° | 59° | 59° | +-------------------+------+------+------+ A--1000 c.c. water plus 40 c.c. Peroxide plus 5 c.c. ammonia B--500 c.c. water plus 2 grams Ursol D (Para-phenylene-diamine) C--500 c.c. water plus 5 grams Ursol D
TABLE III +-------------------+------+------+------+------+ | | A | B | C | D | | | S.P. | S.P. | S.P. | S.P. | +-------------------+------+------+------+------+ |_Salt-acid Tan_ | C. | C. | C. | C. | |Australian Opossum | 51° | 51° | 53° | 56° | | | | | | | |_Chamois_ | | | | | |Mink | 59° | 59° | 61° | 62° | +-------------------+------+------+------+------+ A--500 c.c. water plus 5 grams ground nut-galls B--300 c.c. water plus 2 grams pyrogallic acid C--500 c.c. water plus 2 grams potassium bichromate D--Water, after treating leather with rapeseed oil
TABLE IV +-------------------+------+------+------+------+ | | A | B | C | D | | | S.P. | S.P. | S.P. | S.P. | +-------------------+------+------+------+------+ |_Salt-acid Tan_ | C. | C. | C. | C. | |Australian Opossum | 49° | 49° | 55° | 50° | | | | | | | |_Chamois Tan_ | | | | | |Mink | 59° | 67° | 69° | 70° | +-------------------+------+------+------+------+ A--500 c.c. water plus 5 c.c. formaldehyde for 1 hour B--500 c.c. water plus 5 c.c. formaldehyde for 12 hours C--500 c.c. water plus 10 c.c. formaldehyde for 3 hours D--As in C, but treated with 500 c.c. water plus 5 c.c. ammonia, instead of water alone.