Cox Thimble Drome Special & Champion info please Or Is there a time line?

Hi, Well, my question is which came first? :-) The Champion or the Special?

I guess the Champion was first with it's Cameron Glow plug engine , and then the Special as the engine is considered the first Cox engine (mostly)

But there are ads that show both the Cox Thimble Drome Champion & Special on the same page.

The Thimble Drome Champion seems to just have come in 2 versions, powered and non powered, yes, in many color combos and chrome versions.

And there were quite a few variations of the Special Pusher (Non powered), with the fake exhaust pipe, and with out, different casting variations, Grill area, and different chassis widths, and there was an uncommon Clockwork wind up motor variation.

And I have never seen non powered Champion or Special packaging...

Any way, I find this all fascinating, but can not find a definitive time line for the creation and release dates of Roy Cox's first metal toy cars... I do know late 1940s it to the early 50s..

If any one has knowledge or where to find such info, it will be appreciated :-) thank you , ~Myk

Here is a timeline from Martin Hepperle's website. Obviously a Cox fan. For some reason it is hard to link straight to the Cox info in his site.

Use this link to open his site then click on Cox engines on the left of page. Now your in the Cox info page click on "model database" then cars.
http://www.mh-aerotools.de/airfoils/index.htm