NavList:
A Community Devoted to the Preservation and Practice of Celestial Navigation and Other Methods of Traditional Wayfinding
Re: "A history of marine navigation" by Per Collinder, and Neckam
From: George Huxtable
Date: 2009 Jul 17, 18:29 +0100
From: George Huxtable
Date: 2009 Jul 17, 18:29 +0100
I had questioned Collinder on the accuracy possible with pendulum clocks on land in the mid 1700s, and Ken added- | | In WJH Andrewes "Quest for Longitude" there is a chapter on Harrison's | regulators by Martin Burgess where it is claimed that he was able to keep | time to one second in three months; the limit achievable with a pendulum | in air clock. I don't think Tompion's regulators ever went better than 2 | seconds per week, but that figure is from memory and could very well be | wrong. Quite so. I doubt if that claim for one second in 100 days, for Harrison's regulator clocks, is accepted by all authorities, but he had certainly made great strides in the precision of pendulum clocks. Tompion's earlier clocks suffered from being before the days of temperature-compensation of the pendulum. George. contact George Huxtable, at george@hux.me.uk or at +44 1865 820222 (from UK, 01865 820222) or at 1 Sandy Lane, Southmoor, Abingdon, Oxon OX13 5HX, UK. --~--~---------~--~----~------------~-------~--~----~ NavList message boards: www.fer3.com/arc Or post by email to: NavList@fer3.com To , email NavList-@fer3.com -~----------~----~----~----~------~----~------~--~---
