This was a talk in person by Jeremy Batch.
A synopsis of the presentation is given below.
Swinging, Spinning and Wobbling: pendulums, gyroscopes and Inertial
Navigation – a talk by Jeremy Batch
“I can dive off the eastern coast of the United States and surface again in the Mediterranean within five hundred yards of where I expect to be,” says Rock Hudson to Patrick McGoohan in Ice Station Zebra. We would take that for granted today, but how was it even imaginable in 1963 when Alistair Maclean wrote the book, and was the captain (or the author) exaggerating?
Our world is round (sort-of) and takes 24 hours (almost) to revolve. The roundness was
obvious to sailors for centuries, but the size of the sphere (if, indeed, it was a sphere) was a matter of guesswork and its rotation was once a dangerous heresy. The tilt, wobble and lumpy shape were all puzzling, but eventually undeniable.
We shall meet: Léon Foucault, demonstrating the Earth’s rotation with pendulums and gyroscopes which stay fixed relative to the universe; Hermann Anschütz-Kaempfe, using the rotation to align his gyrocompass, and Elmer Sperry (allegedly) copying his ideas; leading to Charles Stark Draper and his rivals developing inertial navigation for ships, submarines, missiles, aircraft, spacecraft and cars, allowing us to travel confidently to the Moon and across its surface and (more daringly) beneath the North Polar icecap and through the Limehouse Link tunnel.
And as the Royal Navy tests Birmingham University’s quantum inertial navigation system on XV Patrick Blackett, ready for when GPS says “0 satellites available”, should we be saving our pennies or polishing our sextants?
This was a well attended meeting and the audience look forward to seeing future presentations from Jeremy. We will try to book Jeremy for a future presentation in 2025.
The main part of the evening was a presentation of a cheque to the Chairman of the RNLI Hitchin & District Branch of the RNLI, John Pearce. 
