CONTENTS 



part I. 



PAGE 



THE CENTENNIAL CELEBRATION OF THE ACADEMY, May 26, 1880 



1 



Part II. 



I. The Tortugas and Florida Reefs. By Alexander Agassiz 107 



II. The Apparent Position of the Zodiacal Light. By Arthur Searle 



135 



III. On the Square Bar Micrometer. By S. C. Chandler, Jr 158 



IV. Stellar Photography. By Edward C. Pickering 179 



V. A Catalogue of 130 Polar Stars for the Epoch of 1875.0, resulting from 



all the Available Observations made between 1860 and 1885, and 



REDUCED TO THE SYSTEM OF THE CATALOGUE OF PUBLICATION XIV. OF 



THE ASTRONOMISCHE GeSELLSCHAFT 



By William A. Rogers and Anna 



Win lock 



• - 



227 



VI. Pritchard's Wedge Photometer 



By S. P. Langley, C A. Young, and 



E. C. Pickering 



301 



VII. Memoir of Daniel Treadwell. Bv Morrill Wyman 



325 



