[ 335 ] 
XII. 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 Ouclh. 
Communicated by H. F. Blanford, F.R.S., Meteorological Reporter to the 
Government of India. 
Received January 3,—Read January 20, 1887. 
[Plates 19-21.] 
In the 13 years which have elapsed since Mr. Blanford published his paper 
on the Winds of Northern India,* very great additions have been made to our 
knowledge of the meteorology of the country. The carefully organised system of 
observations, commenced in Bengal and the North-Western Provinces, has been 
extended to include the whole of India, and placed under the direction of 
Mr. Blanford himself, aided by local officers in all the larger provinces. Verified 
instruments have been supplied to all the stations, and the elevations of these above 
sea-level have been determined by connecting them with the lines of spirit-levelling, 
carried inland from the coast, in various directions, by the officers of the Great 
Trigonometrical Survey; or, where this was impracticable, by spirit-levelling to some 
of the trigonometrical stations of the Survey. In this way, trustworthy and inter¬ 
comparable series of barometric observations, extending over ten years or more, have 
been obtained for all the more important stations. At the same time, the diurnal 
variations of the barometer at certain selected stations have been determined by long- 
con tmued series of hourly observations, with the object of enabling us to reduce the 
readings made in the ordinary way (usually at 10 a.m. and 4 p.m.) to true daily 
means. Simultaneously with the collection of this immense quantity of accurate 
and reliable barometric data, observations have been made of temperature, humidity, 
cloud, wind, and rain. Latterly also barometric and wind charts of the Bay of 
Bengal have been prepared from observations made on board ships navigating those 
waters. 
During these 13 years, the winds prevailing over the Indian continent and the 
Bay of Bengal, and their relations to the distribution of pressure at sea-level, have 
“ The Winds of Northern India,” by Henry F. Blanford, F.G.S. ; ‘ Phil. Trans.,’ vol. 164, 1874, 
Part II. 
16.11.87 
