It is an extraordinary experience for me to write a 'report' about Leon I-leppel.
As the most influential teacher in my own career, I'm sure he has written about
me often.  Eut I have not previously been called upon to write about him.  Some
of my thoughts about Leon are put down here.  They convince me that he should
have the support of the Guggenheirn Foundation.  I am hopeful that the Committee
of Selection will agree.

an individual some years older than the specified age.  For at least twenty years,
Leon himself has Jokingly complained about the effects of age and ageing on his
ability to work.  All the while, he has grown progressively younger, and worked
progresslvely harder,  The fteld of nucleic acid biochemistry had his attention
for 15 years.  During that time, he made fundamental contributions to the under-
standing of enzymes that function wfth nucleic acids as substrates and developed
the methodologies which are still being used and ampl4fieQ.  It is important to
realize that in the early 1950s, when he began working on nucleic acids, almost
nothing was known about their structure, enzymology, or metabolism.  Leon's lab
drew a series of visitors anxious to learn techniques and ideas.  The group
i ne1 uded Mars ha1 1 Gi renberg and H I Gobi nd Khorana .

posttfon as a senior, respected individual in the field, Leon moved to another
'undeveloped' area in the mid 1960s.  This was the field of bacterial cell mem-
branes and transport of metabolites across the membranes,  Again, he made
fundamental contributions both to methodology and to mechanisms.  Again , other
investigators have come to him to learn,

Now it seems that Leon is once more interested in a change in direction.
Characteristically, his brief sutmerry In the reports you sent to me goes,
succinctly, to the heart of some very messy and confuslng data,  Also charac-
teristically, he has set forth a straightforward and perceptive outline of
how order night be made of the many observations.  The heart of the outline
Js in the proposed experiments, not In a discussion.

I suppose that the Cmittee is especially interested in why it should support

In spite of the many remaining interestlng problems, and in spite of his

Age, then, is an trrelevancy when considering Leon.  h'is constant involve-
ment in new ideass his unfaltering belief that the strength of science is In
experimentatton, his unflagging ability to spend long hours at the bench --
all these speak to his youth.  It 9s only those of us who try to take him as
a model and keep up wfth him that are exhausted.  The Guggenheim Foundation's
money could not be better spent.  Leon will surely accomplish important
thlngs, and the people in Stoker's laboratory will have an unequalled oppor-
tunity to find out what a scientist should be like.