I recently received an email from clock maker Bernie Tekippe of Atlanta Georgia. Bernie makes his own design of precision regulator which is capable of accuracy of .008 +/- seconds per day. Bernie had read my article on the Negus marine chronometer #1273 in the Sept/Oct 2015 Bulletin. He wrote to tell me he liked the article and of a lecture he attended many years ago given by the late Dana Blackwell. Blackwell was commenting on the Venus transit expeditions and that he learned the "box" chronometers used on that expedition preformed better than many of the precision regulators some of the scientists elected to use. While the observatory instruments could normally out preform the portable chronometers they needed their massive concrete support bases and temperature controlled rooms to gain the advantage. In the field and set up on less than perfect platforms they were not capable of their inherent accuracy or performance. This no doubt because of the very sensitive to disturbance pendulums they used.This is where the more portable and more robust box marine chronometer had the advantage. How would it have ever been possible to survey and explore the American West without the portable and accurate box chronometer? While designed for navigation at sea the marine or box chronometer found many other uses. These timekeepers were, when properly adjusted, capable of keeping very accurate rates of time and certainly good enough for successful navigation at sea, hydrographic/ geographical survey work and scientific expeditions.
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