Das Picnic: Vexierbild / Picture Puzzle Advertisement for Dr. August Koenig's Hamburger Tropfen

On one side is a picture puzzle titled "Das Picnic," with the words "Wo ist der Mann, welcher stets Dr. August Koenig's Hamburger Tropfen gebraucht?" in old German script below. The reverse side describes the product and provides directions and cautions for its use. The product was (most likely) manufactured and sold by A. Vogeler & Co., of Baltimore Md. [From the Internet: August Vogeler was born in Germany in 1819, and emigrated to the United States in his twenties. In 1874 he established a drug business in Baltimore and manufactured products such as Dr. August Koenig's Hamburger Tropfen.] At the bottom of the card is printed: F. M. Findeisen, New Cassel (Fond du Lac County), Wis. [Internet searches show that Frederick Maximilian Findeisen was born around 1836/1837 in Prussia and arrived in New York in 1862. That same year he married Ernestina in Fond du Lac. He naturalized as an American citizen in 1865. He owned a grocery store ("Dealer in Dry Goods, Boots & Shoes, Hardware & Groceries") in New Cassel, which may have been built in 1874, and he served as the New Cassel postmaster in 1868. He died in 1905, and is buried in Campbellsport, Fond du Lac County, Wisconsin.]