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Date
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29 MAY 2013
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Time
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18:00 - 20:00
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Event Type
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Associated Society
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Seismology, in the sense of the observation of earthquakes and speculation about their nature, has a longer history in Britain than many people might imagine. It may come as a surprise to learn that the oldest theoretical writing on earthquakes in Britain dates back to the end of the 12th century. The first attempt in Britain to make a properly scientific study of an earthquake was as early as 1666.
Speculation on the nature of earthquakes in the historical period was to a large extent driven by individual events, especially those felt in London (in 1580, 1692 and 1750) or of a particularly catastrophic nature (as in 1693 – Val de Noto, Sicily - and 1755 - Lisbon). Reading these early works today brings home how hard it was to make accurate deductions about causes from very limited observational data. Writers such as John Flamsteed and William Stukely constructed very plausible sets of inferences about earthquake mechanisms that were nevertheless quite wrong. The first author who made a positive advance in earthquake theory was John Michell, who in 1760 deduced that earthquakes were transmitted as waves in an elastic medium.
Instrumental seismology also started early, with what was almost certainly the world’s first local network of seismic instruments deployed in Perthshire in the 1840s. These inverted pendulum instruments were the invention of James Forbes, developed for an earthquake investigation committee of the British Association for the Advancement of Science. The committee was chaired by the amateur seismologist David Milne (no relation of John Milne) who also made macroseismic surveys, compiled a British earthquake catalogue, and whose theoretical writings on earthquakes are not without interest.
Seismological investigation later in the 19th century was mostly macroseismic in nature, with highlights being the investigations conducted by Robert Mallet, Edward Lowe, Raphael Meldola and William White, and the massive world earthquake catalogue compiled by Mallet and his son.
However, it was the work of John Milne, the centenary of whose death is marked in 2013, that had the largest international impact. Milne started his career as an engineering geologist, and accepted a university appointment in Tokyo in 1876. While in Japan he developed an interest in earthquakes, and played an important part in seismometer design at the end of the 19th century. On his return to England, he established for the first time a global earthquake recording network, centred on his observatory at Shide, Isle of Wight.
Milne’s composite bulletins, the “Shide Circulars” developed, in the 20th century, into the world earthquake bulletins of the International Seismological Summary and eventually the International Seismological Centre, which continues to publish the definitive earthquake parameters of world earthquakes on a monthly basis.
Seismic recording stations in Britain for most of the 20th century were run on an ad hoc basis by interested individuals, often amateurs. It was not until 1975 that a coherent national seismic monitoring network was begun, by the Institute of Geological Sciences (now the British Geological Survey). The task of recording and publishing earthquakes in Britain is now entrusted to BGS, supported by a customer group of national and local government, industry and other interested parties.
Non-members of the Society are welcome to attend.
Please note that there is no charge to attend the Lecture.
Seats are allocated on a first come, first served basis.
Tea and biscuits will be served from 5.30pm - 6pm.
The lecture will be followed by an informal reception.
Tickets for the reception are available from the SECED secretary, price £10.
For further information please contact the SECED Secretary at the ICE on:
Tel: +44 (0) 20 7665 2229, or Email: secretary@seced.org.uk
Visit the SECED website at http://www.seced.org.uk