Leo Yaffe
1916 - 1997

Dr. Mike Attas, of the Whiteshell Laboratories of Atomic Energy of Canada Limited, wrote the following obituary of Dr. Leo Yaffe, who died on May 14, 1997.   Dr. Attas earned his doctorate in Classical Archaeology and Chemistry from McGill University, as Dr. Yaffe's last doctoral student.

Leo Yaffe, pioneer Canadian radiochemist, died in Montréal last week.   His scientific career spanned the entire breadth of the Canadian atomic energy program from its wartime origins to the present day.

Born in Devil's Lake, North Dakota, raised in Winnipeg, and educated at the University of Manitoba and McGill University, Dr. Yaffe was asked to help in wartime nuclear research in 1943.   He participated in Canada's Atomic Energy project first at Montréal and then at Chalk River.   He became project leader in the Nuclear Chemistry and Tracer Division, as well as Mayor of Deep River for two years.   He made fundamental measurements of neutron absorption cross-sections, half-lives, and beta-radiation energies for isotopes such as carbon-14, sodium-24 and cobalt-60, and determined the yields of the most common products of uranium fission (I, Xe, Cs and Ba isotopes).   Many of AECL's earliest reports bear his name.

Leo Yaffe returned to McGill in 1952 to teach and to set up Canada's foremost university research lab for radiochemistry.   In his career there he supervised 39 graduate students and almost as many post-docs, in fundamental work on beta measurement techniques, production of uranium-233 from thorium, and proton-induced fission.   More recently his scientific interests included the use of nuclear methods to provide archaeological information such as the age and place of origin of artifacts.

Professor Yaffe has served his profession as Director of Research and Laboratories at the IAEA in Vienna, as Chairman of McGill's Department of Chemistry, as Vice-Principal of Administration, and as President of the Chemical Institute of Canada.   He has received numerous awards in Canada and internationally for his excellence as a scientist, teacher, and administrator.   He had a passion for developing peaceful uses of nuclear energy and for communicating scientific results to a broader public.   His classic lecture "The Health Hazards of Not Going Nuclear" always drew a crowd of technical and laymen alike, and gave him a chance to discuss controversial subjects in a clear and rational manner.

Dr. Yaffe gave a talk when he visited AECL's Whiteshell Laboratories in June 1984.   Mike reports "Dr. Yaffe had a packed audience in Building 300, and kept them spellbound for 60 minutes of talk and 30 minutes of questions.   I was hosting it and reluctant to break in, since everyone seemed to be having such a good time.   The following write-up (author unknown) appeared in the June 22 1984 edition of the Whiteshell Nuclear Research Bulletin:


Dr. Leo Yaffe  was part of the brilliant international team of scientists who made history in wartime Canada with the Montréal Atomic Energy project - the project that eventually grew into AECL.   He came to WNRE this week to describe what it was like.   In a seminar to WNRE employees, he called his participation in the group beginning in 1943, "the most exciting time of my life".   "Never before had such a talented group of scientists gathered in Canada with such a single mission."   "Working with them, many of whom were of Nobel Laureate calibre, was like doing 20 post-doctoral fellowships simultaneously," he said.

He also said that, considering there were many refugee scientists from so many different countries, it was remarkable how little internal friction there was - although it took the Canadians some time to establish themselves as "ordinary citizens" and not "colonials who did things in curious ways".   Dr. Yaffe noted that when the work was in progress the refugee scientists saw the weapons potential of their results much more than did the Canadians.   The Europeans "had heard the tramp of invading armies in their homelands," he observed.

Dr. Yaffe, now Professor Emeritus at McGill University, isn't much impressed with the present-day tendency towards decision by committee - he completed his talk with a cartoon from the New Yorker showing a father and son studying a statue of several people on a pedestal.   "You see my son", the caption reads, "there are no more great men and women; only great committees".   He applauded men like C.D. Howe, then Minister of Munitions and Supply; Sir John Cockroft who was brought from the Cavendish Laboratories in England to run the Montréal project; Dr. Chalmers Jack MacKenzie, then head of NRC and AECL's first president, a man who recognized the peacetime potential of atomic energy and insisted Canadians be trained in it.   He called these men "real decision makers".   "They consulted and then they moved and most of the decisions they made, besides being courageous, were right.   We could never have gotten this far without them and we owe them a debt which we sometimes forget," he said.

Dr. Yaffe wanted part of the record set straight - why the refugee scientists, for whom the Cavendish labs were then a mecca, came to Canada.   It was not, as many historians claim, because we had uranium.   The British government wanted the team to move here to escape heavy bombings in the U.K., and because they hoped their proximity to the U.S. would encourage the Americans to collaborate in this research, so vital to the war effort.   He also said that when he joined the group in 1943, collaboration with the U.S. was virtually zero.   "This turned out to be very fortunate indeed, because as a result we did our own science and engineering and did it extremely well," he said.    He feels there is a movement today among Canadian bureaucrats to revert to conventional prewar wisdom on science.   He described it as mission-oriented research and the importation of technology.   He promises us that this will take us back to industrial colonialism" and "third class status in the world".

For security reasons, scientists with this mission weren't allowed to keep diaries and notebooks and, as a result, Yaffe says, it is the least recorded period of our scientific history.   However, he noted the opening of the archives after 30 years has stirred interest in the Montréal project and, in recent months, two historians have interviewed him.    He has hope that the fascinating story of nuclear science in the forties will be told.


During his talk, Dr. Yaffe mentioned the Ernest Rutherford museum housed in the Macdonald building at McGill.   Rutherford was the brilliant New Zealander who did so much pioneering nuclear research.   Yaffe said that he found it "very exciting" to study the exceedingly simple equipment, much of it homemade, with which Rutherford worked, knowing it was used to discover alpha and beta rays and determine the nature of radioactive materials.   "So little money was available and great ingenuity was used", Yaffe said.   He also praised McGill for recognizing Rutherford's genius and bringing him, at 27 years of age, to Canada as a full professor.   Rutherford won the Nobel prize in 1908, the year after he left Canada for Manchester, for work he had done at McGill.

Glenn Seaborg and Leo Yaffe (Chemistry in Canada June 1982)

Further reading on the late Dr. Leo Yaffe:

In Memoriam - Leo Yaffe: Researcher, Teacher, Administrator and Citizen    from the McGill Reporter, May 29, 1997.

Leo Yaffe, FCIC, OC (1916-1997) - University Teacher, Researcher and Administrator Par Excellence.   A tribute to the legacy of a nuclear chemist from a colleague. Canadian Chemical News, Jan 1999 pp 25-27 (pp. 7 - 9 of the pdf file).

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