Unusual and interesting antique hold to light (HTL) litho printed card

Images on two sides with captions in German

One side depicts a woman milking a cow, holding a bottle up to the cow's udders

The other side shows a woman feeding a paper with the same bottle

Made in Germany 

Card measures 5 1/2 x 3 5/8"

No odors, wear along edges, bottle contains a gritty substance that probably used to flow like milk when the card was tilted,

cow side of card has a small tear/missing triangle and clear piece of tape affixed

Sold as shown, see photos

Estate sale find