Miscellaneous Papers. 365 



of the skins that I have collected in the field were cured in such an 

 improvised tan-vat with good results. 



SKINS IN THE MUSEUM. 



At the University we look over skins as soon as they reach the 

 laboratory, wash those that are dirty, and place them in tan-liquor 

 for immediate safe-keeping. After a few days they are examined 

 and moved about in the tan- vats. As soon as we are ready to work 

 upon the skins they are hung on poles, a few at a time, over the 

 tan vats and allowed to drain until the tan-liquor ceases to drip 

 from them. Then they are taken to the laboratory, where they are 

 redressed. To dress the skins they are spread over half-round tim- 

 bers, or tanners' fleshing beams, and shaved and scratched with va- 

 rious kinds of knives and scrapers, the hack-saw being one of the 

 useful tools used. Thick skins, like those of the walrus or the 

 necks of such animals as the elk, moose or buffalo, are shaved until 

 they are thin and of an even thickness. All bones are removed 

 from the feet of the skins except the bones that fit in the claws of 

 such animals as the fox, beaver or bear. I have learned from ex- 

 perience that it is dangerous to leave even a small toe bone in any 

 kind of a skin, especially of the larger mammals. In time, if the 

 skin has been dried, grease may come out of the bone and stain or 

 rot the skin. If the skins are kept green in tan-liquor this may 

 not occur, at least for several years. 



TAN-LIQUOR. 



Museum men and taxidermists are not agreed upon what con- 

 stitutes the best tan-liquor. Some advise using nothing but salt 

 brine. I have tried salt brine for ten years, but not with the beet 

 success. It sometimes allows skins to get "slippery," so to speak. 

 Some use salt brine with sulfuric acid in it — even as much acid as 

 an ounce to a gallon of brine. My experience has gone to show 

 that this is too much acid for museum skins. It seems to destroy 

 the fiber of the skins, particularly if the skins are left in it very 

 long. Skins kept for one year in such a tan- liquor were very tender. 

 A little acid — say one ounce to ten gallons of salt brine — enough 

 to keep it sweet, so that it would not get slippery, might do; but I 

 prefer to use a little alum in the tan-liquor and leave the acid out 

 altogether, especially where skins are to remain green in tan-liquor 

 for several years. Where skins are to be tanned for rugs, they may 

 be placed in a salt and alum tan-liquor that has from one- half to 

 one ounce of sulfuric acid in it. However, skins should not be left 

 in such a solution for more than from one to three weeks, depend- 

 ing upon kind and thickness of skins. 



