I have a query. Can anyone shed lite on the history of the Time machine and the like.

People say that (no dealers metioned) their version is a ripp-off of (no dealers mentioned). HBowever I'm sure this kind of watch is an old principle, so is it justifiable sayng that a dealer has ripped of somone elses trick.

The "Stull Watch" was the original, by Bob Stull in California in the 1940's. Everyone else's is a variation on the theme.
Did you know you can do a "time prediction" with an ungimmicked "Swatch" brand wristwatch?
Don't know who discovered the concept, but it is very effective.

This is correct. The Stull Watch was the original.

Collector's Workshop began producing various versions of this during the 1970's using electronic watches. All of the versions currently on the market are based on one of the CW versions of either "Perfect Time" or "A Gift of Time."

The Swatch Watch trick is claimed by several people, including Bev Bergeron.

There are also ways to do it with other ungimmicked watches.