Unfortunately, I did not have a camera -- or even a smart phone -- with me, so no pictures (I know, it didn't happen!), but I saw two very interesting century-old bicycles yesterday at our town's monthly Classic Car Night.

https://www.encinitas101.com/events/classic-car-nights/

I am normally not a fan of powered bicycles, particularly those with combustion engines, but these two were just plain weird.

The first was a steam cycle, which featured dual chain drive from a steam combustion engine mounted above the crank, and with an exhaust pipe extending upward and to one side.

The second was a triple (three-seat tandem) with a big 4-cylinder gasoline engine sitting atop a reinforced rear rack and driving a big wooden propeller. The inventor reportedly had three sons who were bicycle racers. This fixed gear, brakeless rig required real timework, with the captain in charge of steering and the kill switch, the first stoker controlling the fuel supply, and the second stoker controlling the engine throttles.