The years have been kind to you Andre 
I thought the tie and polished shoes would distract you but nothing escapes your eagle eye. Oh well, back to the drawing board.
Basically, the photo I sent is a penny-farthing design turned inside out with the farthing (a quarter-penny) dispensed with in the interest of economy. It could be called the "safety" version of the penny-farthing, in the same way that the first bicycles with two more or less equal-sized "small" wheels were called "safety bicycles" because when they crashed it was a shorter distance from the saddle to the road rash.
I probably should stress that while all this sounds humorous, the large unicycle with the rider inside the wheel is a proven design that demonstrably works all the way up to big block hemiheads and other excesses, ridden by big-hog thrill-seekers on American streets.
In case the question has already arisen in your mind, How do you steer the thing? Simple. You lean over, as you do on a bicycle. That means a rounded tyre, so it has no innate stability at rest.
I've ridden a penny farthing, from a museum in a parade, and can tell you I'd much rather hug the ground from inside the wheel than sitting on top of it. The next year I fixed up the museum's early Mercedes (Daimler-Benz) to drive* in the parade instead, and the curators sighed in relief because at least I wasn't going to fall off it in one of their precious period costumes and rip it.
* The biggest deal wasn't mechanical at all because the car was pretty much in as-new condition, tended by a permanent engineer who lived over the stables until it went into the museum about forty years before I was born -- it was acquiring the esoteric information necessary for starting and operating the car. On one of my rides I go faster downhill on my bicycle than double that car's top speed...
PS BTW, Andy, I love "Glastonbury Special": instant image of some kind of eccentric, the tension and mystery sustained while one discovers what kind of eccentric.
