This was on display at the Heritage Day display at the O'Hara Mill Homestead and Conservation Area in Madoc, Ontario.
According to Indestructables.com:
"The Donalson Jockey Cycle was manufactured in Kansas City in the 1940's for about 4 years from 1944 until 1948 by the J.E. Donalson Manufacturing Company. According to local newspapers in the area, the company's most notable product was the Donalson Jockey Cycle, a tricycle that was ridden like a horse rather than pedaled. The company also made bicycle, tricycles and some airplane parts for the US Military during World War II.
The Jockey Cycle is a most unusual tricycle, since it has two large rear wheels and a very small front wheel. What makes it even more unusual is the way it is powered. Instead of the usual rotary pedals, the Jockey Cycle has a bar that is pushed down on with both feet. This turns the rear axle crank which rotates the rear wheels. Another unusual feature is the saddle/seat to moves up and down when the wheels turn, giving the rider the feeling of riding a horse."
The company seems to have run out of ideas for products, based on a 1944 ad they ran in Popular Mechanics:
Follow the link above to see this thing in operation. Very cool!