I started making saddles in the mid 1960's, and it was still fairly common to use dextrin or cellulose paste to keep the woolskins in place on skirts. But as earlier posts have stated , there was the problem of the wool coming loose later. Sometime after being wet the woolskins could stretch and become loose on the skirts. So now I use rubber cement on both new and repair linings. I still use dextrin paste on swell covers, horn covers and back cantle covers. To stop molding of the paste, I add a spoonful of rubbing alchohol, and use an airtight container. Seems to keep for a prolonged period of time without any mold forming.