A treatise on new philosophical instruments for various purposes in the arts and sciences. With experiments on light and colours / By David Brewster.

  • David Brewster
Date:
1813
Catalogue details

Licence: Public Domain Mark

Credit: A treatise on new philosophical instruments for various purposes in the arts and sciences. With experiments on light and colours / By David Brewster. Source: Wellcome Collection.

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    seventeen secondary planets; the determination of the figures and revolutions of several of the ce- lestial bodies ; the transits of the inferior planets over the sun; the successive propagation of light; the aberration of the celestial bodies ; and the structure of the starrv heavens ; are a few of the additions which Astronomy has received from Tie science of Optics. In the prosecution of these discoveries, the micrometer became a powerful auxiliary to the telescope. It enabled the practi- cal astronomer to measure, with accuracy, the smallest spaces in the heavens, to determine the diameters of the planets, and to ascertain those minute changes in the form and position of the celestial bodies, which have led to the most im- portant informat ion respecting the oeconomy of the heavens. When we contrast the rude measure- ments of Kepler and Tycho with the delicate ob- servations of Bradley, Maskelyne, Herschel, and Schroeter, we cannot fail to perceive the advan- tages of the micrometer, and the effect which any further improvement upon it must ultimately have, in contributing to the progress of the most per- fect of the sciences. In the present advanced state of Astronomy, every thing depends upon the accuracy of obser- vation. The quantities to be ascertained are fre-