ee) 
TRANSACTIONS OF THE foot. 14, 
The Secretary presented verbally the minutes of the preced- 
ing meeting. 
There being no business, the Section of Astronomy and Phy- 
sics immediately organized, and listened to the first paper of 
the evening by Pror. Harotp Jacosy, entitled “ The Reduction 
of Astro-Photographic Plates.” 
This paper was read by title, and was explained as being a 
discussion of the best formule for the reduction of the photo- 
graphic plates selected by the International Committee for the 
Photographic Mapping of all the Heavens. It will be published 
as a bulletin of the Committee at Paris. 
The second paper was read by R. S. Woopwarp: “ Results 
of Experiments on Metallic Spheres Falling in Water.” Prof. 
Woodward, after detailing various attempts to obtain data upon 
the law governing the motion of spheres in liquid, reported 
the results of a preliminary series of experiments, made at Co- 
lumbia College last June. The experiments were performed by 
dropping spheres of steel, silver, aluminum and platinum in a 
tube of water sixteen feet long and one foot in diameter. The 
spheres varied in diameter from one inch to two inches. The 
interesting results of these preliminary tests are that all the 
spheres acquired a constant velocity inside of the first metre. 
Newton’s law that resistance to motion is proportional to the 
square of velocity seemed to be verified. The times of falling 
were determined with a hyppchronoscope. 
More elaborate experiments with the same apparatus will be 
made later. This paper was discussed by Prof. Jacoby and 
others. 
W. Hattock reported upon some Summer work upon 
the action of the vocal chords in voice production, and described 
the photographs taken of the chords while in action, illustrative 
of their operation. 
The Academy then adjourned. 7 
Wo. HALLock, 
Secretary of Section. 
