Answer: I am assuming this cartoon is about the Prohibition from 1920-1933.
Explanation: In the prohibition the 18th amendment became law which banned manufacturing, transporting, importing and selling alcoholic liquors in the United States. The people who did sell it were called Bootleggers and they had to transport the liquor in cars that were modified so that they could get away from the law quickly. They also used cow shoes when transporting liquor so that they would not leave footprints that could be detected by the law.