1891. ] NEW YORK ACADEMY OF SCIENCES. 95 
the observation on a systematic plan of the comparison stars used 
in the observations of planets and comets, and for which satisfac- 
tory catalogue places cannot be found. 
-Sidereal System, On the Theory of the, proposed by Mr. Maxwell Hall. 
By W. E. Plummer. II., 45. A review and examination of Mr, 
Hall’s paper published in the 43d vol. of the Memoirs R. A. S., in 
which the author attempts ‘“‘ to connect Proper Motion with Annual 
Parallax, and with the radial velocity of the fixed stars.” From 
the tests which he applies to Mr. Hall’s theory, Mr. Plummer re- 
gards the latter’s results as inconclusive and untrustworthy. 
*Telescopic Stars, Christian Mayer’s Observations of, arranged according 
to Constellations (H. C. F. C. Schjellerup). III., 57. 
VI, SPHERICAL ASTRONOMY, 
Polhéhe, Ueber eine Methode die, mdglichst frei von systematischen 
Fehlern zu bestimmen. Von Prof. J. C. Kapteyn. III., 147. 
‘Precession, Constant of, A New Determination of the. By J. L. E. 
Dreyer, Ph.D. II., 185. Contains a description of the previous 
labors of Bessel, Struve, and Nyrén on this subject. Dr. Dreyer 
takes as the basis of his work Lalande’s ‘“ Histoire Céleste” and 
Schjellerup’s catalogue of 10,000 stars, and deduces a result which, 
for 1800.0, is only 0’’.0046 less than the Struve-Peters constant. 
Right Ascensions, Lalande’s, Note on the Accuracy of. By J. L. E, 
Dreyer. III., 103. 
VII, THEORETICAL ASTRONOMY, 
A Comparison of Le Verrier’s Tables of Uranus and Neptune with 
lee by Newcomb of the same Planets. By David P. Todd, M.A. 
+) 239. 
Kepler’sche Problem, Ueber das. Von Prof. J.C. Kapteyn. III, 25. 
Keplere Remarques concernant le Probléme de. Par M. R. Radau. IIL, 
132. 
‘LLambert’schen Gleichung fiir parabolische Bewegung, Ueber die Auf- 
lésung der. Von Prof. W. Klinkerfues. I., 5. 
Problems der Drei KOrper, Eine neue Behandlung des. Von Dr. H. 
Kobold. II., 69. 
Problem der Drei Kérper, Bemerkung zu Dr. H. Kobold’s Aufsatz tiber 
das. Von Prof. Aug. Weiler. II., 130. 
Special Perturbations, Note on the Computation of. By Ormond Stone, 
II., 120. 
‘Theorie der Bewegung der Himmels-Ko6rper, Prof. Gyldén’s Neue Un- 
tersuchungen iiber die. Von Dr. O. Backlund. I1I., 203. 
Wabhren Anomalie, Ueber den zweiten Differentialquotienten der. Von 
W. Klinkerfues. II., 163. 
Wahren Anomalie genommen, Ueber den zweiten Differentialquoti- 
enten von x nach der. Von August Weiler. III., 16. 
VIII. ASTRONOMICAL BIBLIOGRAPHY, 
‘“Cycle,” A few Addenda to Admiral Smyth's (Editors). II., 93. 
Manuscript der Pulkowaer Sternwarte, Ueberein altes. Von A. Wagner. 
II., 128. An Arabian manuscript containing data concerning the 
annual increase in the mean longitude of the sun, from which M. 
