604 
PHILOSOPHICAL SOCIETY OF WASHINGTON. 
49th Meeting. January 23, 1889. 
The Chairman, Mr. Doolittle, presided. 
Present, fifteen members and guests. 
The annual election of officers of the Section was held and 
resulted in the choice of Mr. R. S. Woodward for Chairman and 
of Mr. A. S. Flint for Secretary. 
Mr. A. S. Flint presented a paper on, A Brief Control for 
General Solutions of Normal Equations. 
Published in full in the Annals of Mathematics, 4to, University 
of Virginia, Va., Dec., 1888, vol. 4, No. 6., pp. 182-185. 
Mr. Artemas Martin read a paper on Napier’s Logarithms. 
Published in full in the Mathematical Magazine, edited and 
published by Artemas Martin, 4to, Washington, vol. n, No. 1, 
Jan., 1890, pp. 4-6. 
Mr. W. F. McK. Ritter made a communication on General 
Perturbations of the Minor Planets. 
50th Meeting. February 6, 1889. 
The Chairman, Mr. Woodward, presided. 
Present, thirteen members and guests. 
Mr. C. H. Kummell made a communication on An Error of 
Delaunay which has Passed into Text-Books and Encyclopedias. 
Mr. J. H. Gore made a communication on The Scope and 
Character of a Bibliography of Geodesy now Completed. 
The bibliography referred to is published as Appendix No. 16 
of report of U. S. Coast and Geodetic Survey for 1887,4to, Wash¬ 
ington, Government Printing Office, 1889. 
Mr. M. H. Doolittle made a few remarks on The Applica¬ 
tions of a Formula for the Probability of an Event Resting on 
the Concurrent Testimony of Two Witnesses. 
