On occasion, you will find a Warner’s Safe Cure with its label in tact along with some of its contents. In some instances, the top of that bottle may include a proprietary tax stamp similar to the one below.
I wrote about these little gems back in 2008. They were originally used to generate revenue to offset the costs of the Civil War, but later evolved into a means that patent medicine manufacturers, like Warner, used to assure the public of the genuineness of their product. Note the warning on the stamp below: “NOT GENUINE IF STAMP IS BROKEN”.