7th March, 1955
Dear Jim,
Many thanks for your letter.  Robley Williams's new E.M. work is certainly exciting and convincing.  I had heard about the visible threads, from several sources, but not about the work on polymerised protein X.
I've been doing various things since I last wrote, and hope to write up some of them soon, and send a manuscript to you.  I've been developing the idea of a grooved contour and estimate the depth of the groove, to be of the order 15 A.  This leads me to suspect a reversal of the normal size distribution between the 2nd and 3rd non-origin maxima on the equation.  It is not clear from your letter whether this agrees with Casper's signs or not.  Do you include the central maxima in the sign distribution you give? My guess is 0(+), l(-), 2(+), 3(+).   It would be nice to know whether this is the same as Caspar's series, which was derived by totally different reasoning.
I have also got some good photographs from cucumber virus (from Knight) and from a different strain of TMV (2 from Siegel at U.C.L.A.)  They show some quite interesting points of difference.
More recently I've had some of Commoner's B8 which does quite exciting things.  It expands like a stretched spring when in water - by about 15 percent.
When are you coming over here?
Best wishes,
Yours