250 Library, [Dec. 



and is determined by the temperature of rapidly ascending moist but 

 unsaturated air rising with the maximum temperature at the level 

 of the plains. As the rate of decrease of temperature of such con- 

 vective currents is about 1° for every 200 feet, the temperature at the 

 elevation of 6000 feet above the plains of the Punjab would be about 

 72° (the ordinary minimum temperature of the Punjab in fine weather 

 in January) minus 30° (i. e. 3 £-^-) or 42°, which is 6° higher than the 

 average minimum temperature in the plains in January (viz. 36°). 



About sunset at a hill station in such weather tempei'ature de- 

 creases rapidly until it has reached the temperature corresponding to 

 the same level above the plains. There is at night a slow and steady 

 flow from the hills downwards to the plains which gives rise to a flow 

 towards the hills from the corresponding elevated strata above the 

 plains. This source of comparatively warm air is so large that the air 

 coming from it maintains a neaidy constant temperature during the 

 night at the hill stations and gives them a night temperature as high 

 and sometimes higher in such weather than at the plain stations. This 

 explanation hence accounts not only for the high minimum temperature 

 at night but for the cold period of rapid cooling about sunset which is 

 a very chai'acteristic feature of the hill station. 



The paper will be published in the Journal, Part II. 



h 



IBRARY. 



The following additions have been made to the Library since the 

 meeting held in December last. 



TRANSACTIONS, PROCEEDINGS AND JoUI^NALS. 

 presented by the respective Societies and Editors. 



Angers. La Societe d'E'tudes Scientifiques dAngers, — Bulletin, 1887. 



Berlin. Der Koniglichen Akademie der Wissenschaften zu Berlin, — ■ 

 Abhandlungen. 1888. 



— — — . Der Koniglich Preussischen Akademie der Wissenschaften zu 

 Berlin.— Sitzungsberchite. Nos. 22—38. 1889. 



Brisbane. Royal Society of Queensland, — Proceedings, Vol. VI, Part 5. 



Brassels. L'Academie Royale des Sciences, des Lettres et des Beaux- 

 arts de Belgique, — Annuaire. 1888 — 1889. 



i . . Bulletins. (gH» Serie) Tome XIV— XVII j 



1887—1889. 



__ 1 . Memoires. Tome XLVII, 1889. 



