Abstract
WHEN Newton's “Principia” raised the theory of astronomy to a height not previously dreamt of, practical astronomy was still where Tycho Brahe left it almost a century before. Such was the respect paid to the memory of that great man that Hevel in Danzig carried out Tycho's ideas about his observatory, and rejected all the improvements that had since originated, amongst which was the application of the telescope to astronomical observations. The obstinacy with which Hevel refused to adopt this invention appears strange to us now, but we must remember the great accuracy which was then obtained by pinnules alone. Tycho had reduced the probable error of astronomical observations from ten minutes to one, and some of Hevel's observations have been found to be affected by errors of less than half a minute of arc, results which show that the old astronomers were in possession of a skill in handling their apparatus which has since been lost. It should also be taken into account that the telescopes of Hevel's day were generally of Dutch construction, and Kepler's tube, with wires in the field to mark the centre, was first brought into general use by Auzout and Picard about the end of the century. Of hardly less importance was the application of the pendulum to clocks, which from that time have been used as astronomical instruments. They had in Tycho's observatories been used merely to show what o'clock it was when observations were made, but never to determine differences of right ascension.
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DOBERCK, W. Ole Römer . Nature 17, 105–108 (1877). https://doi.org/10.1038/017105a0
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DOI: https://doi.org/10.1038/017105a0