This page is a record of our activities in the 2018-9 session together with relevant notes added after the activity.
24 September 2018
Are we alone in the Universe?
Terry Sloan – Emeritus Professor of Physics, Lancaster University
Our programme started with an excellent talk from Professor Terry Sloan on the possibility of intelligent life elsewhere in the Universe, including the Search for Extra-terrestrial Intelligence (SETI) programme and the search for exo-planets, the probability that intelligent life exists elsewhere in the Universe and what is special about our Universe that has allowed life to develop. He also briefly touched on the possibility that ours is one of multiple parallel universes.
28 October 2018
James Hutton, the Father of Geology
James Hutton (1726-97) was a Scottish polymath who flourished during the Enlightenment in the second half of the 18th century, at the final emergence of western civilisation from the middle ages. When he was born, the creation myth was still the orthodoxy and, although Newtonian physics was widely accepted, chemistry had hardly emerged from alchemy and heat was still a mysterious subject.
He had a great interest in the rocks that he saw around him, and his observation of the similarity of sedimentary rocks to aspects of the present day landscape led him to formulate his theory of the Rock Cycle, describing how rocks formed. His theory still stands substantially unaltered today, but at the time there were two main obstacles to its acceptance:
- He rejected the orthodox view of the age of the earth but could only make qualitative estimates; indeed serious quantitative estimates only appeared in the second half of the 19th century and were continually
revised well into the 20th century.
- He could not propose a physical mechanism for the rock cycle. It needed the advances in the understanding of chemistry and heat that took place during his life-time for him to suggest a plausible mechanism. But it was not accepted until long after his death.
His life is interesting not only for his contributions to geology but also for the light that it throws on the struggle during the Enlightenment to reach a rational view of the world.
Following his talk Jonathan offers suggestions for follow-up reading.
Stephen Baxter. Revolutions in the Earth: James Hutton and the True Age of the World. Weidenfeld & Nicholson, 2001. ISBN 0297 829750. The main source for the talk, and very readable.
Donald B McIntyre and Alan McKirdy. James Hutton: The Founder of Modern Geology. National Museums Scotland, 2012. ISBN 978 1 905267 736. A pleasant, content-light hagiography.
Rachel Laudan. From Mineralogy to Geology: The Foundations of a Science, 1650 – 1830. University of Chicago Press 1987. ISBN 0226 469476. A sceptical view of the British origin of the science, and (justly) critical of Hutton’s methodology.
Charles Lyell. Principles of Geology 1830. Available on Kindle (abridged). Surprisingly readable.
26 November 2018
Stewart explained what AI is and how it works. It was particularly fascinating to see examples of its use in different fields such as the identification of cancer tumours and driverless vehicles.
28 January 2019
Colour and colour vision
Brian took us through the structure of the eye and how we see, particularly the mechanism involved in colour vision. He discussed colour sensitivity and the effect of faulty colour vision. He included colour effects from white light, including prism effects and rainbows, together with subjective aspects, including optical illusions in colour. A lively discussion ensued on the primary colours of colour addition for light and why they are different from those involved subtractively in paints.
25 February 2019
Waste and Recycling in South Lakeland
Andrew Vickers (South Lakeland District Council)
In an unusual approach questions were taken at the beginning of the talk and Andy then concentrated on answering these questions for us. We learned how there is no further manual handling of our waste after it gets into the recycling vehicle and why this means that all plastic, except polythene film, is recycled. While it's disappointing that food waste is not currently recycled to do so would require significant capital investment from the Government that may come in the next few years. The philosophy taken by SDLC is to make recycling simple for the householder. Examples Andy gave include "if it looks like plastic put it in the blue bag" and that envelopes with windows can be included in the paper bin. However separating paper and card into different layers in the paper bin is a help to the people on the collection lorry since they are separated at this point. We also learned that SDLC has one of the best recycling rates in the UK, to a large extent since householders do an excellent job of separating at source.