1891. ] NEW YORK ACADEMY OF SCIENCES. 41 
Mr. Frank M. CHAPMAN was nominated as a Resident Member 
by Proressor J. A. ALLEN. 
The Astronomical Section then organized, Proressor J. K. REEs 
in the chair. Mr. Jacopy, the Secretary, read the following papers 
by title: 
I. Transit Factors for the Observatory of Columbia College. 
BY J. T. MONELL AND C. R. MANN. 
II. The Rutherfurd Photographic Measures of the Group of the 
Pleiades. 
BY HAROLD JACOBY. 
The following papers were then read, entitled: 
Report upon the Meeting of the National Academy of Sciences. 
BY HAROLD JACOBY. 
(Abstract. ) 
At the meeting of the National Academy of Sciences held at 
Columbia College, November 10th to 12th, the following papers of 
a mathematical nature were read: Certain New Methods and Re- 
sults in Opties, by Professor Charles 8. Hastings; New Pendulum 
Apparatus, by Professor T. C. Mendenhall; Astronomical Methods 
of Determining the Curvature of Space, by Professor C. 8. Peirce ; 
Variation of Latitude, by Professor 8. C. Chandler ; Color System, 
by Professor O. N. Rood; Reduction of Rutherfurd’s Photographs, 
by Professor J. K. Rees; Measurement of Jupiter’s Satellites by 
Interference, by Professor A. A. Michelson. 
Professor Hastings’s paper contained some new and very simple 
demonstrations of optical formule already known, as well as certain 
important formule altogether new, including a general expression 
for magnifying power applicable to both telescopes and microscopes. 
Professor Peirce presented astronomical evidence tending to show 
that space possesses a negative curvature, and called attention to 
various methods of conducting an investigation of this property of 
space. Professor Chandler exhibited curves showing that the re- 
cently discovered variation of latitude could be made to explain 
certain hitherto unaccountable discordances in older observations. 
His paper was followed by considerable discussion among the as- 
tronomers present, Professors Young, E. C. Pickering, C.S. Peirce, 
Abbe, and Dr. Gould taking part. The chief question debated was 
whether the variation bas a /errestrial or celestial origin. The 
investigations are being published in the Astronomical Journal. 
Vou. XI.—4 
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