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Perhaps this may be of help?

Source: History of Tribology by Duncan Dowson

In History of Tribology Dowson shows a picture of a Chinese cart or chariot with a wooden figure on top.  The figure was connect to a set of gears so that it always pointed in a constant direction.  This cart aided Chinese travelers crossing the Gobi desert where it was difficult to avoid becoming lost.

Found on: http://tribologynews.wordpress.com//category/history/
Philip

On Fri, 2009-08-21 at 20:17 -0700, James N Wilson wrote:

This somehow reminds me of learning some years ago about an ancient
method to maintain orientation while crossing the Gobi desert. Primitive
bevel gears were somehow used on a cart to maintain the orientation of a
statue on a vertical axis. As long as both wheels rotated the same
amount, the statue pointed straight ahead. But if one rotated more than
the other, the statue pointed in a different direction, indicating that
the cart had turned.

Alas, I can't find anything about this now, and my old references have
been lost. But it is interesting, even if I can't now figure out how it
was done. I do remember that it was ingeniously simple.

I'm remembering a bit more. This was offered to me as the first use of
the bevel gear principle, and it was before the internet, so what I saw
was hard copy. I wish I had it now.

Jim Wilson
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