The cosmic ray conference at Bagn`eres de Bigorre in July, 1953 organized by
Patrick Blackett and Louis Leprince-Ringuet was a seminal one. It marked the
beginning of sub atomic physics and its shift from cosmic ray research to
research at the new high energy accelerators. The knowledge of the heavy
unstable particles found in the cosmic rays was essentially correct in fact and
interpretation and defined the experiments that needed to be carried out with
the new accelerators. A large fraction of the physicists who had been using
cosmic rays for their research moved to the accelerators. This conference can
be placed in importance in the same category as two other famous conferences,
the Solvay congress of 1927 and the Shelter Island Conference of 1948
