This is a vintage, antique Citrate of Magnesia Medicine Bottle likely produced in the 1920s to 1930. The Depression Era remedy was sold as a laxative, purgative by druggist such as John H. Martin. of St. Louis, MO. The bottle is likely produced by Martin but I don't see any maker marks other than what may be an Owens glass mark on the bottom. (circled "o".) The clear quack remedy bottle is in great shape, free from breaks or cracks (although there is a tiny nick on the inside lip... See photo closeup). My father, an avid bottle digger, found the bottle more than 40 years ago in the ruins of an old plantation home in Virginia. The bottle measures about 8" tall and 2.5" wide. Please note this is an empty bottle sold for as a collectible.