The June, 1930 issue of Modern Mechanix carried this short article on a "reducing" machine for doggies. It claims to "save wear on husbands."
The contraption, which was first exhibited at the Los Angeles Dog Show, permits the dog to run for an hour without getting anywhere, and the proud owner may be sure that Fido will not get lost. If a rabbit passes by the dog has a good run while bunny stands around nibbling clover. A flywheel supplies momentum.