Flamsteed Astronomy Society

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The exhibit was rounded-out by some demonstrations of technologies key to precision timekeeping.  One model demonstrated the use of ‘isochronous cheeks’ (cue Frankie Howerd) to control the swing of a pendulum and make each swing take the same time regardless of the size, or amplitude, of the swing.   There were also two demonstrations of the use of bi-metals, a technology invented by John Harrison himself and used for temperature compensation in the form of the ‘gridiron’ in his regulator pendulums and in the first two marine timekeepers H1 & H2.  Harrison developed the technology into the bi-metallic strip for his third, fourth, and fifth marine timekeepers H3, 4, & 5.   Bi-metal technology is a speciality of one of the exhibit organisers, John Taylor, inventor of the ‘Taylor blade’, a bi-metal disk still used in its millions as a switch to control electric kettles and toasters etc.

As well as taking their shifts as demonstrators of the pendulum and bi-metal models, Eddie & Mike were also busy during the week strutting their ROG stuff by telling the Harrison and ROG story to many of the visitors.  Good job they like the sound of their own voices!

It was a real pleasure and privilege to participate in such a rare and special event presented in the imposing and significant surroundings of the Royal Society.

 

MRD

“The Excitement of Time” exhibit at

The Royal Society, July 3rd to 6th, 2006

Mike discusses the 1610 Harvey lantern clock (picture Tyra Till)

Eddie explains the bi-metal ‘Taylor Blade’ used in kettles etc (picture Mike Dryland).

Sir Arnold Wolfendale reviewing the exhibit book (picture Mike Dryland)

“Isochronous cheeks, Madame” — Is he allowed to say that? (picture Tyra Till)

The exhibit thronged with visitors of all kinds

(picture Tyra Till)

The Harrison 1725 regulator and Maskelyne info board

(picture Tyra Till)