UNIVERSITY OF ILLINOIS

DEPARTMENT OF BACTERIOLOGY

362 NOYES LABORATORY OF CHEMISTRY
URBANA

November 28, 1951

Dr. J. Lederberg

The University of Wisconsin
Department of Genetics
Madison 6, Wisconsin

Bear Josh:

Thank you very much for your letter of November 25 and the
information that you sent along. We shall begin using this
method and will slowly accumulate somekind of data on the
problem, Needless to say, I would not undertake for either
myself or any of my students the kind of exhaustive systematic
analysis which would put this method on a firm basis. I hope
I'm not bothering you too much, but you mentioned that the
vials you employed possess the catalog number 111, but you
didn't mention what catalog this referred to, This is something
I would like to know. To make things a bit easier I am
enclosing a self~addressed penny post card on which you can
jot down that bit of information, Finally I must confess to

ignorance of one of your terms spelled "bels." What in the
name of heaven is that?

Thanks once again.

a

Sincerely yours,

Set

S. Spiegelman
SS:o2

Ene,