PHILOSOPHICAL SOCIETY OF WASHINGTON. 39 



In this table each current is counted once, and a decided pre- 

 dominance of westerly currents is evident. This is in part ex- 

 plained by the fact that ascensions are made by preference only 

 in settled pleasant weather, i. e. on the front side of an advancing 

 area of high barometer. Ascensions are, however, also made 

 generally in the afternoon, when on our Atlantic coast the sum- 

 mer afternoon sea breeze would tend to increase the number of 

 easterly winds in the lowest stratum of air. 



Mr. King's table gives the currents in the order of their super- 

 position, beginning with the surface wind, and it is rare to find 

 an upper current in a direction opposed to the lowest or surface 

 wind — such generally deviate but 90° -135° from each other. 

 The ascensions have rarely exceeded ten thousand feet in alti- 

 tude, and thus can give us an insight into the nature of only the 

 lower system of currents that precede extended storms. 



From seven balloon ascensions made on July 4, 1811, at differ- 

 ent points in the United States, I have deduced the velocity of 

 the upper currents as about four times that of the surface wind 

 then prevailing. 



18th Meeting, January 13, 18Y2. 



The President in the Chair. 

 Mr. W. Harkness read a paper 



ON THE density OP THE HYPOTHETICAL RESISTING MEDIUM IN 



SPACE. 



(This communication is published in Washington Astronomical Observations y 

 1870, Appendix IL, pp. 33-38.) 



Mr. T. Gill read a communication 



ON THE TAPIR OF THE ANDES AND ITS ALLIED FORMS. 



Mr. R. D. CuTTS presented a paper 



ON THE MISAPPLICATION OF GEOGRAPHICAL TERMS, AS BEARING 

 ESPECIALLY ON THE QUESTION OP THE INTERPRETATION OF THE 

 FISHERY RIGHT TREATIES. 



