It says POISON and shows a skull and cross-bones, so I'll throw it in here.
It's badly faded, but this is a Muriatic acid bottle from Smith's Drug Store of Muskegon, Michigan, and is believed to be one of the few with the label on the original bottle.
Someone found a bunch of labels from this company (which was around for a long time) and threw them on old bottles, so it's rare to verify an original.
It annoys me so much when people sell random bottles with NOS labels on them. At least it's usually pretty easy to tell the NOS labels from the ones which were actually used. Yours definitely looks legit.
Indeed a real one there.
Try to pick up one of the new old stock labeled bottles and display it with yours.
Let people handle the altered one, it will be easier to read, and make your real one "pop" displayed with it.
Yep an Elmer's glue stick. Sometimes the best solution is the simplest one. If you want to needlessly pay more for some museum quality adhesive go ahead. I've used glue sticks on early 1900's bottles...