The model is based on the 1930 Meccano Super Model No.33/33a Single and Double Fly boats. This was a fun model to build and operate, it was one of the first models I built when getting back into Meccano as a hobby. It was in fact beyond the scope of my Number 10 set hence some of the non matching parts. The drive on my version is by Meccano cord running around the circumference of the wheel and with a over crossed belt on a pulley driven by a Temsi 300 motor,  very similar to the Meccano/Märklin power drive motor. I built it as an excuse to use my then newly purchased girder frames p/n 113 a lovely part with not too many uses! I made small cabins instead of the "Fly boats"  used on the original model these did not somehow look right with the massive structure of the supporting frame. Someday I will get around to building the double one published in the same SML leaflet with two contra rotating wheels. A similarly proportioned but smaller model that I have also built appeared in the Meccano Magazine Model of the Month in December 1957 this model has in addition a rotating base. You can find several other Big Wheels on my web pages I have built in recent years. The original model was sprocket chain driven, was not very practical in such along length, see original illustration above from SML No.33 leaflet. The use of a cord gave a very smooth and steady drive. I think that a sprung idler against the chain would have overcome the problems I perceived at the time. New picture and text January 30 2008 Text revised March 23 2021 .