Opel-RAK were a series of rocket vehicles produced by Fritz von Opel, of the Opel car company, in association with others, including Max Valier and Friedrich Wilhelm Sander largely as publicity stunts.
The Lippisch Ente a rocket-powered glider was produced on June 11, 1928, piloted by Fritz Stamer, but is not usually considered part of the series.
Opel RAK.1 - a rocket car that achieved 75 km/h (47 mph) on March 15, 1928
Opel RAK.2 - rocket car May 23, 1928 reached a speed of 230 km/h (143 mph) driven by 24 solid-fuel rockets
Opel RAK.3 rocket train (quoted speed is variously 254 or 290 km/h. See: , , , , ) On the second run the train jumps the track and is destroyed.
Opel Rak IV rocket train, destroyed when a solid rocket explodes on the track, exploding all the other rockets. Railway authorities prohibit further runs.
Opel RAK.1 rocket glider September 30, 1929
Some stock footage of some of the rocket vehicles was incorporated into this early SF film.
Here is an old British toy that had a lot of good intentions, but also some unanticipated drawbacks.
Buildings were constructed on allegedly waterproof waxed card bases. The bricks etc. were stuck together with a mortar made from a mixture of flour and chalk powder. It required a great amount of skill to erect buildings accurately, very time-consuming and beyond the patience of most of the children it was aimed at (8 to 14 years). Especially so in cold houses (as most British homes then were) it would take several days for the building to 'set'. Reusing the components involved a process of dunking the entire model in a large bowl of warm water. After the model fell apart the bricks and plaster pieces required lengthy rinsing to remove all organic traces to prevent mould growing on them.
I wonder how well they sold in the USA, as touted in the ad below, from Boys Life for September 1948.
If you took a three-wheeled motorcycle and dropped the shell of an auto atop it, this is what you would get. Lift the hood of the "car," and there is the engine riding on a single steerable wheel of its own
We marvel at films like Rudolph the Red-nosed Reindeer, or Wallace and Gromit, in which, during a given scene, one or two puppets might be in motion. I can't fathom the amount of work that Joop Geesink went through to create his films.