I wonder if this one has ever been brought to the attention of the members
of this group.

Look at this picture of the discoverers of the chemical structure of DNA:
http://www.uwinnipeg.ca/~simmons/DNA/sld008.htm
(better versions may be found on the web or in recent articles)

In this very famous picture, probably taken in 1953, as James Watson is
observing him, Francis Crick is pointing to a model of DNA with an object
that apppears to be a slide rule.

Does anyone know what model of SR is pictured here?

Considering that the team discovered the molecular structure of DNA while
working at the Cavendish Laboratory in Cambridge, do you think that the
model of SR that Crick is holding might be a Unique model, or does anyone
recognize another make?

(In his Nobel lecture, Crick omitted to specify what model SR he was using
at the time... ;-)
http://www.nobel.se/medicine/laureates/1962/

François
______
http://www.boucher.cc/