March 31, 1959

Professor J. Rotblat

The Medical College of St. Bartholomew's Hospital
Charterhouse Square

London, E.C.1, England

Dear Professor Rotblat:

I appreciated receiving the invitation of
the Pugwash Continuing Committee to participate in a private

meeting to consider problems of biological and chemical
warfare.

Unfortunately, I will not be able to fit this
into my schedule and am obliged to decline.

Yours sincerely,

Joshua, Lederberg
Professor of Genetics