PROCEEDINGS OF THE ACADEMY AND AFFILIATED 



SOCIETIES 



THE PHILOSOPHICAL SOCIETY OF WASHINGTON 



The 724th meeting was held on April 12, 1913, at the Cosmos Club. 

 President Abbot in the chair; 55 persons present. ' The minutes of the 

 723d meeting were read and approved. 



Mr. R. S. Woodward presented a paper on The laws of falling bodies. 

 The history of the subject, beginning with the first consideration of the 

 problem by Gauss and Laplace 110 years ago, was reviewed. These 

 investigators differed in their conclusions, Gauss maintaining that there 

 is a meridional deviation towards the equator, which Laplace denied. 

 Poisson made some corrections to Gauss's work but accepted his con- 

 clusions, as did most of the subsequent workers. In view of conflicting 

 opinions, differences in experiments, and of obvious defects in the mem- 

 oirs, the speaker has thought it worth while to study the subject further, 

 taking into account the recent work in geodesy. The method of La- 

 grange was used to derive the equations. The height of fall was limited 

 so that there wovild be no exterior effects on account of other bodies. 

 Discussion of equations was carried to terms of the second order and 

 some results of the application of the formulae given. The conclusion 

 reached was that the deviation in the meridional plane due to the rota- 

 tions and figure of the Earth is towards the north. The easterly devia- 

 tion is very much larger than the northerly. There is need of more 

 information regarding the geodesy of the subject. The paper was dis- 

 cussed by Messrs. Bauer, Littlehales, Wead, and Rosa. 



Mr. C. W. Waidner spoke on Sea water temperatures iyi the vicinity 

 of icebergs, giving results of the experiments carried out by a party of 

 three from the Bureau of Standards on a United States cruiser. The 

 thermometer was a flat rectangular nickel coil enclosed between two 

 copper plates pressed close to the side of the ship and connected to a 

 Leeds and Northrup recorder. The equipment and charts showing some 

 of the records were illustrated by lantern slides. So far as detection 

 of proximity of icebergs is concerned, the general conclusion was that, 

 while such records may be of help, the normal variations are generally 

 so erratic and large in comparison with effect due to icebergs that it 

 is practically impossible to get definite indications from the records. 

 Other experiments made on salinity and density of sea water indicated 

 that nothing could be accomplished, as the diluting effect is infinitesimal. 

 The paper was discussed by Messrs. Bauer, Littlehales, and Burrows 

 as to the radiation method from the surface of icebergs and by Mr. 

 Abbot. 



J. A. Fleming, Secretary. 

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