ISEN-ASTC-L is a service of the Association of Science-Technology Centers
Incorporated, a worldwide network of science museums and related institutions.
*****************************************************************************

Here's another, simpler, lateral-thinking approach that might well work,
again assuming that the sand is in a circular enclosure. Mount an external
electric motor centrally above the top, with ordinary dust-seals on a
vertical shaft projecting down above the sand.

Instead of a fan, simply fit flat, radial 'paddles' to the end of the shaft
to drive the rotating wind.

I wonder if anyone has tried that?

Promoting public engagement with science
through a contagious delight in phenomena
*
[log in to unmask] * http://www.interactives.co.uk
*
http://uk.linkedin.com/pub/ian-russell/0/636/305
*
Give people facts and you feed their minds for an hour.
Awaken curiosity and they feed their own minds for a lifetime.
*
Ian Russell

***********************************************************************
For information about the Association of Science-Technology Centers and the Informal Science Education Network please visit www.astc.org.

Check out the latest case studies and reviews on ExhibitFiles at www.exhibitfiles.org.

The ISEN-ASTC-L email list is powered by LISTSERVR software from L-Soft. To learn more, visit
http://www.lsoft.com/LISTSERV-powered.html.

To remove your e-mail address from the ISEN-ASTC-L list, send the
message  SIGNOFF ISEN-ASTC-L in the BODY of a message to
[log in to unmask]