Presented by: 
Neil Boucher
Date: 
Tue 17 May, 6:00 pm - 7:00 pm
Venue: 
Goddard 8-139

The transatlantic cable was the first really expensive (>$1,000,000 ; read $100 million plus in today’s dollars) electrical technology undertaking. It was cutting edge to the extent that no one could be sure that it was actually feasible. After a number of unsuccessful (and very expensive) attempts a viable cable was finally laid in 1866.  Much of the recorded history of this enterprise is merely a rehash of the news reports of the day. This talk looks to reconstruct the project of the cable from the perspective of the designers, and the science both good and bad.

To assist in the reconstruction we will look at an authentic, working Thompson mirror galvanometer (see picture below), of the type used on the cable. Its sensitivity sets some limits on the cable parameters. We also demonstrate the way in which the galvanometer was used as the receiver.  Thompson (Lord Kelvin) was a major player in this project.