Holcomb, Fitz, and Peate: Three Nineteenth Century American Telescope Makers

Holcomb, Fitz, and Peate: Three 19th Century American Telescope Makers

Robert P. Multhauf The telescope was invented about 1600. It was brought to America about a half-century later, and within another century had become a commonplace appurtenance to the library of the cultivated gentleman.[1] Throughout this period, from Galileo to Herschel, the telescope found use in scientific astronomy, although the possibility of contributing to the science of astronomy by simple observation diminished continuously after the time of Galileo. Herschels work had aimed at the advancement of scientific astronomy through increasing spectacularly our powers of vision, just as had that of Galileo in the 17th century and of Hale in the 20th. But even in Herschels time the monstrous size of the instrument required made the project something of a national effort. The telescopes of the 18th-century American gentleman were already toys, as far as the astronomer was concerned. However, the telescope had another, if less glamorous, use in the 18th century. This was its use in positional astronomy, in the ever more precise measurement of the relative positions of objects seen in the heavens. Measurement had been the purpose served by pre-telescopic astronomical instruments, the sighting bars of the Ptolemaic observers of Alexandria and the elegant quadrants of Tycho Brahe. For a time[157] after the invention of the telescope the professional astronomer resisted the innovation, but by the end of the 17th century the new optical instrument was being adapted to the quadrant and other instruments for the precise measurement of the positions of heavenly bodies in relation to the time-honored astronomical coordinates. By the late 18th century telescopes were found serving three relatively distinct purposes: the increased magnification of the sky in general (in which use Herschels 48-inch reflector had made all others obsolete): the more precise measurement of planetary and stellar positions (and, conversely, of the Earths shape) by means of the quadrant, vertical circle, zenith sector, and similar instruments; and the simple edification of the educated but not learned classes, who wished not only to see what the astronomer saw, but to have an instrument also useful for looking occasionally at interesting objects on earth. ......Buy Now (To Read More)

Product details

Ebook Number: 58747
Author: Multhauf, Robert P.
Release Date: Jan 21, 2019
Format: eBook
Language: English