Perhaps a slightly different question from the norm...
Do any of you have any helpful suggestions for the following?
I'm teaching a course here (Cornell) on the history of mathematics,
and the students have to investigate some topic in reasonable depth.
One of them is very interested in finding out about mathematics/
number/astronomy in pre-roman celtic/gaelic/breton/cornish/etc times.
I've done a typical gopher and library search, but didn't find anything
terribly obviously helpful. I'd be very grateful if one (several) of
you kind folk could steer me in a more fruitful direction.