SENIORS GROUP
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LUNCHTIME RENDEZVOUS: Clubhouse
Wednesday the 25th of March 15
From 1000 to 1500 hours
Location:
Clubhouse, Daniel Stewart’s and Melville College
Inverleith Playing Fields, 523 Ferry Road, Edinburgh
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Programme:
1000
1025
1030
Arrival and coffee/tea [first floor]
Welcome and Introduction by the Seniors Group Coordinator [ground floor]
Lecture The Ozone Hole by Emeritus Professor Arthur P Cracknell, formerly
Carnegie Professor of Physics, University of Dundee, Dundee, Scotland
[ground floor].
1125 Lecture Musical Instruments by Professor Donald Murray Campbell, Senior
Honorary Professorial Fellow, School of Physics, University of Edinburgh,
Edinburgh, Scotland [ground floor].
1220 Four Course Lunch with Wine (Waitress Service) with partners and friends [first
floor].
1500 Finish
This Lunchtime Rendezvous is primarily a social occasion for the Seniors Group but the
talks are intended to be of interest to all. Over coffee and lunch there will be an
opportunity to discuss possible future events of interest to Members.
The cost is given on the Booking Form and includes coffee and a four course lunch with
wine. Non Members are most welcome to attend. Please note that the completed
Booking Form must be received by the Seniors Group Coordinator by the date shown on
the Booking Form.
Abstracts:
The Ozone Hole by Emeritus Professor Arthur P Cracknell, MA, MSc, DPhil, FInstP,
FRSE, FRSPSoc, formerly Carnegie Professor of Physics, University of Dundee,
Dundee, Scotland.
Ozone is a trace gas, a very minor component, in the Earth’s atmosphere; in fact
there are only about three ozone molecules in every 10 million air molecules. One might
suppose that such a minor constituent of the atmosphere would be of very little
importance to us, but this is not the case. In particular the thin layer of ozone in the
upper atmosphere shields us from ultraviolet radiation from the Sun which is a major
cause of skin cancers in humans, particularly pale-skinned humans.
The concentration of ozone in the atmosphere has been reducing in recent years as
a result of human activities, principally the manufacture and use of CFCs
(chlorofluorocarbons) as refrigerants and in aerosol sprays cans. This ozone depletion is
particularly dramatic in the Antarctic spring and is described as the ozone hole. This talk
will narrate the story of the ozone hole, its discovery, its causes and attempts to repair the
damage.
It will be necessary, first of all, to describe some of the properties of ozone in the
atmosphere, its production and destruction in a pre-industrial un-polluted atmosphere and
its role in screening the Earth from solar UV radiation. Then there came man-made CFCs
and once these gases were released into the atmosphere they severely affected the
atmospheric ozone. The CFCs have caused two effects, the first is a general decline
(depletion) in ozone concentration all over the Earth (but least in the tropical regions) and
the second is the spectacular ozone hole that occurs each spring over the Antarctic and, to
a lesser extent, over the Arctic. The discovery of the ozone hole led to intense
international political activity leading to the Montreal Protocol which is an international
agreement which seeks to restore the atmospheric ozone layer.
Musical Instruments by Professor Donald Murray Campbell, BSc, PhD, Senior Honorary
Professorial Fellow, School of Physics, University of Edinburgh, Edinburgh, Scotland
Although the scientific study of music goes back at least as far as the ancient
Greeks, there are still many important aspects of the working of musical instruments
which are not yet fully understood. Does it matter what wood a woodwind instrument is
made of? Was there a mysterious secret that enabled Stradivarius to make such wonderful
violins? Why does a brass instrument sound brassy? These and other questions will be
explored in the talk, which reviews the basic physics of sound production in string, wind
and percussion instruments.
There is a lively international research community working in musical acoustics,
and some recent advances in understanding the often subtle relationship between the
physical properties of an instrument and the musician's evaluation of its quality will also
be reported. The presentation will be liberally
illustrated by live performances on several orchestral instruments, and also on some more
exotic examples including the alphorn, the serpent and the great bass rackett.