The mysterious Lowell Railroad flask

I recently bought a half pint historical Lowell Railroad flask on eBay. It was a mysterious flask because it had some sort of contents in it and the "cork" was frozen in place. I posted it on Facebook pages dedicated to the conservation of glass history and I had many mixed emotions on if I should take the cork out. I decided it wouldn't hurt. I hit it for 30 seconds with the "hot" setting on the hair dryer and the cork wiggled out. Inside, we found shreds of a VERY old dishcloth and a mysterious (tasteless) white powder.  We cleaned up the bottle and replaced the cork. It is now an amazing sparkly piece of 1830's glass. It has amazing character and thousands of tiny air bubbles near the surface that look like glitter. Posted below are before (eBay pictures) and after pictures.