"John B. Bunch" <[log in to unmask]> writes:
>Robin,
> The materials you are looking for are called
>"pola-tape." A small motor with a rotating polarized filter
>was attached to the bottom of an overhead projector lens: the
>parts of the overhead transparency where the tape had been
>applied gave the optical effect of liquid motion. Las I know,
>there was a company in King of Prussia Pennsylvania marketing
>these things but I do not have a name or addr.
> It used to be fairly common in the Audio-Visual field.
>If I can get more information, I will let you know.
Contact Edmund Scientific, I'm sure they have this in their
catalog.
Glen Jensen