Here’s an ad from the August 25 1931 edition of the Toronto Daily Star.
Not sure why they singled out baseball, but here we are. King of Pain!
Wikipedia has an entry on Minard’s Liniment. The liniment was apparently created in Hants County, Nova Scotia, in the 1860s by Dr. Levi “The King Of Pain” Minard. The active ingredients are camphor, ammonia water, and medical turpentine. Not to be taken internally.
A geocaching website has an article on Levi Minard. At the age of 52, he graduated from the Eclectic Medical College in Cincinnati, Ohio.