July 5, 1960

Dr. Van R. Potter
Mc Ardle Memoria 1 La bora tory
The University of Wisconsin
rhe Medical School
Madison 6, Wisconsin

Dear Van:

It was very kind of yoa to send me your latest modification of

the DNA model.  I have had a chance to study it and play with it a
little.
connections, I find it awkward to use the models for instructional pur-
poses.
usefulness to the average student to warrant the extra expense and
complication.
keep the double strand together fix the model in such a way that single
nucleotide units cannot be put in or taken out.

While it is a most ingenious way of showing the hydrogen bond

I seriously doubt that these modifications will be of sufficient

     Another limitation is the fact that the two wires which

I'd like to tell you again how popular and valuable the models

were in our general biochemistry course.
tide pairs gratia and invited those who wished to build a large-scale
model to buy their own.
a class of about one hundred.

We distributed four nucleo-

On this basis, we sold fifty or more models to

With warmest regards,

Sincerely yours,

Arthur Kornberg

AK: e 8