Linda Freeman wrote:
What the hell is a Dan Henry?!

Roxie Redlight

The following is completely quoted from Sheldon:
http://www.sheldonbrown.com/gloss_ha-i.html

Dan Henry Arrow
Dan Henry was a very influential cyclist in the '50s and '60s. He is
most famous for the "Dan Henry Arrow" an arrow painted on the
roadway with a stencil or a spray can, as a way of giving directions
for organized rides. Many recreational bike clubs use Dan Henry
Arrows to mark their recommended routes.
He also did a lot of pioneering work on suspension designs for
bicycles, and deveoped a bicycle seat that was based on an
upside-down dropped handlebar with furniture webbing wrapped between
the two straight sections.

He was also known for roller demonstrations where he would perform a
strip-tease while riding on the rollers. A very cool guy.