Bumper Cars - Controversy

QUESTION:  Who received the first patent ever granted by the United States government?  HINT: He received it on July 31, 1790 for a process to make potash (a form of fertilizer). 
A). Samuel Hopkins
B). Oliver Evans
C). Frances Hopkinson
D). Benjamin Franklin

Controversy and drama surround many of the most important inventions created by man. The fight between Thomas Edison and his direct current electricity and George Westinghouse and his alternating current is a famous one, as is the debate over to whether Enrico Marconi invented wireless communication or was it in fact Nikolai Tesla who did it?  One that few people have ever considered on par with these two is the bumper car.  Was it first invented by a man from General Electric named Victor Levand, or did it first come to be in Massachusetts, the brainchild of Max and his son Harold Stoehrer? We may never know the answer to this final question with complete certainty, but we do know that the Stoehrers submitted the first patent application for the bumper car.  It was patent #1,373,108 (remember that, it will be on the quiz later). It was filed on December 7, 1920, and issued the following March 29th.  Their patent application described an electrically-charged thrill ride for amusement parks. It had an electrically-charged ceiling, as well as conductive floors, each with a separate power polarity. This formed a complete circuit and compelled the bumper cars to move, thanks to a pole that extended up from the car and contacted the ceiling.

The cars themselves were generally pretty small, and originally made out of tin. This made them fairly vulnerable to denting upon impact with other cars. It was not uncommon that operators would have to nail the cars back together after being driven. The cars were 'rear-steered,' which made it difficult to control where they went, often softening the blow upon impact, but not enough to reduce the fun factor. The rides were considered unmanageable and jarring by critics, but they did not dissuade people from climbing into them. People loved them, especially kids who might not have had the opportunity to drive anywhere else, and they quickly became one of the more popular attractions at amusement parks and carnivals.  

ANSWER:  A). Samuel Hopkins.  But really, with a hint like the one we gave you, how could anyone have thought otherwise, since Samuel Hopkins was easily the most famous potash producer in the country between July 30 and August 1, 1790!