Lego mono-wheel. This is made of only 20 Lego pieces. The tire is one of the largest one ever made by Lego.
The drive mechanism removed from the tire: the white box contains a 9V battery
This unfinished steam tricycle was parked outside the building.
Close up view of the single cylinder engine. It looks like it is made from a heavy duty pneumatic or hydraulic cylinder.
The red drum is the boiler (propane fired, I think).
A peak inside the boiler: it uses water tubes just like "instant" water heaters. I suspect that this part is an old instant water heater.