A Simple Apparatus for Showing the Movements of the Stars and Ascerting Time or Direction by Means of them.

摘要

108,927. Smith, K. R. Sept. 25, 1916 Stars, ascertaining time from.-Apparatus for showing the movements of the stars and ascertaining time by means of them comprises a circular star chart with the North or South pole at the centre to which is attached a marker or indicator. The stars and constellations, the lines of Right Ascension, and the circles of Dedication are marked on the chart A. in the usual way. The days of the year are marked round the margin of the chart opposite the points of Right Ascension corresponding to the ordered time at midnight. The marker B of cat-gut, silk cord, &c., may be used to mark the meridian of the observer, and it may carry a clip C which may be placed at any point on the margin of the chart. For observation at any other hour than midnight the chart is rotated under the marker B the required number of hours before or after midnight. The Right Ascension of a star can be read on the hours and minutes graduated on the chart by drawing the marker over the star to the margin of the chart. A celluloid or like marker shaped and marked to indicate the zenith and prime vertical for various latitudes may be shaped either as shown in Fig. II or Fig. III.