Reports on Observations of the Total Solar Eclipse of December 20, 1870 (Paperback)

This historic book may have numerous typos and missing text. Purchasers can download a free scanned copy of the original book (without typos) from the publisher. Not indexed. Not illustrated. 1871 Excerpt: ... over the Anapus River. The measurements were made on December 20, with my Chesterman's metallic tape-line, which is too long in the proportion of 100.134 to 100.000. This explains the origin of the column, "Corrected distances," in the following table giving the details of the measurement of the base-line: The following table gives the results of the successive steps in reducing this base to a straight line: On December 20 and 21, Professor Hall and I executed, upon this base, the triangulation shown in Fig. 5, which is drawn on a scale of 1 to 15,000. The different stations are designated in the figure by numerals, as follows: 1 is the Stone Gun-Platform, the position of which is described on page 48. 2 is the Light-House on Maniace Castle. 3 is the highest point in the center of the faqadc of the cathedral, which in ancient times was the Tem ple of Minerva., 4 is the cupola of the Chiesa del Collegio. 5 is the north end of the base, which is directly above the key-stone in the east face of the central arch of the three-arched bridge. 6 is the south end of the base, which is directly above the key-stone in the east face of the arch of the bridge over the Anapus River. 7 is the Belvedere Tower, which is not shown in the figure. By means of my pocket sextant, Stackpole & Brother, No. 346, the following angles were measured: By correcting these angles in accordance with the method of least squares, and then converting them into directions, the corrected directions given in the third column of the subjoined table were obtained. In order to facilitate the adjustment of this triangulation by the method of least squares, I have adopted the following notation: Retaining the numerical designation of the stations already given, two numbers written one...