1887.] Some Anomalies in the Winds of Northern India. 35 



January 20, 1887. 



Professor STOKES, D.C.L., President, in the Chair. 



The Presents received were laid on the table, and thanks ordered 

 for them. 



The Right Hon. the Lord Halsbnry was admitted into the Society. 

 The following Papers were read : — 



I. " Some Anomalies in the Winds of Northern India, and their 

 Relation to the Distribution of Barometric Pressure." By 

 S. A. Hill, B.Sc., Meteorological Reporter to Government, 

 North- Western Provinces and Oudh. Communicated by 

 H. F. Blanforl, F.R.S., Meteorological Reporter to the 

 Government of India. Received January 3, 1887. 



(Abstract.) 



In this paper the author points out that notwithstanding the great 

 amount of light thrown upon the circulation of the atmosphere over 

 Northern India by the accurate and intercomparable barometric and 

 other observations made at numerous meteorological stations during 

 the last thirteen years, there are still some unexplained anomalies 

 connected with the wind system of that part of the world. The 

 most important of these anomalies are the following : — 



(1.) The winds of the hot season not infrequently blow against a 

 rising barometric gradient, i.e., from places where the pressure is low 

 to others where it is higher. 



(2.) The velocity of the wind has little or no relation to the 

 distribution of pressure, but increases and diminishes with the tem- 

 perature. 



(3.) An unusual accumulation of snow on the North-west Himalaya 

 during the winter and spring months causes, as Mr. H. P. Blanford 

 has shown, unusually strong dry westerly winds over the plains during 

 the succeeding summer ; whereas the high pressure at sea-level 

 accompanying cold over the regions to the north of India should 

 give rise to easterly winds. 



The paper is divided into three parts in which these three anomalies 

 are discussed in order. The first part is in reality a train of inductive 

 reasoning which leads irp to the hypothesis that the cause of the 



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