Carnegie Institution
Cold Spring Harbor (L.I.-N.Y.)
April 16th 1958
Dear Dr. Lederberg,
Thank you for your letter dated March 6, that I found on arriving at Cold Spring Harbor last month.  I knew that Stocker had tried transduction by phage in Salmonella but without success.  I have been more lucky and I got colicinogenic transfer by phage lysates.  It is however not very efficient and selection of the transformed cells is at the limit of my technical possibilities.  I am now trying transduction by phage with coli strains.
I am now arranging for my travel in June.  I expect to arrive in Madison by June 9th at 1 or 2. p.m. and spend the afternoon with you.  I hope that this date will be convenient for you because my program is very tight as I have only one month to travel to California and back, and it would be difficult to alter the plans.
Are you going to the Chicago Meeting of the S.A.B.?  I shall be there and hope to meet you.
I am very sincerely yours
[ . . . ] Fredericq