Thanks for the reminder. I caught a bit of it before I turned in the other night, and forgot all about next day. What I saw of it looked really good, about how boat building changed with the fist GRP hulls, and stuff like that.
The launching of the rather boxy canal cruiser was one of my father's Otter amphibious caravans. Raymond Baxter had one. Bought back happy memories of Thames cruising.
Loved it, thanks for posting!
Pity it was only the prototype, all the other 250odd ones had a stern cockpit, as in the film, where the engine (an Anzani 3hp) was outside. The vid was from 55 and that is my mother in the fetching blue trews.