March 27, 1956

Dear Chive:

I haven't the time instantly to write you all the news I owe you, and
am so befogged I can't remember whether I may already have written you
this request, but we urgently need a new batch of serums (H: i, b, 1.2,
enx) and would mich appreciate the favor again.

What the befogment and hurry is about is simply that we've just moved
back into Genetics, after spending since Thanksgiving at the Bactertology
Building. Meanwhile they've remodelled our labs, somewhat as follows.

This is a mugh more efficient layout, with some innovations such as built in
ring-oblique light illuminators in the desks.

The main scientific news that would interest you, I think, is the completion
of the phase variation analysis. It looks juite definite that H, exists in two
hereditary "states", '‘epistatic*® and 'hypostatic! if you like, #hich are res-
ponsible for phase-2 and phase-1 respectively. The> main experiment behind this
is 3. abony —x S. typhimurium (and vice gersa) in the four combinations (donor,
recipient, phase-l and ph-2), in the presemce of anti-i and 1.2. You get the
following set of results (and the qualitatite summary is remarkably well backed
up by the counts):

abony 1 ™2 // abonyl M2 // abony 2? M1 // abony 2 ™ 2

b:1.2 nothing b:1.2 and i:enx dsenx

Presumably, in the cases where one of the two transduction results is missing,
(or both) it comes out in the wrong phase, e.g., i:enx, which is syppressed

by the serum. We have direct substantiation o’ this for inactive "bh", by expts.
involving the Fla-H, linkage, and selecting only for Fla*. We wish we had a
similar linked marker for Hn» but don't,

Did you get the Pereiman book? Actually I bought it for you for Xmas 1954,

but insisted on reading it myself before sending it on to you. And thanks

for so much trouble in transhhpping Brighton Rock: Now we know what it is.

Best wishes, etc,

Sincerely,