Appendix F. WINDS. TEMPERATURE. 403 



radiation * and wind. Broad grass-plots and a gravel walk surrounded 

 the house, and large trees were scattered about ; on three sides the 

 ground sloped away, while to the north the spur gently rose behind. 



Throughout the greater part of the year the prevailing wind is 

 from the south-east, and comes laden with moisture from the Bay of 

 Bengal : it rises at sunrise, and its vapours are early condensed on 

 the forests of Sinchul ; billowy clouds rapidly succeed small patches 

 of vapour, which rolling over to the north side of the mountain, 

 are carried north-west, over a broad intervening valley, to Dorjiling. 

 There they bank on the east side of the spur, and this being partially 

 clear of wood, the accumulation is slow, and always first upon the 

 clumps of trees. Very generally by 9 a.m., the whole eastern sky, from 

 the top of Dorjiling ridge, is enveloped in a dense fog, while the whole 

 western exposure enjoys sunshine for an hour or two later. At 7 or 

 8 a.m., very small patches are seen to collect on Tonglo, which 

 gradually dilate and coalesce, but do not shroud the mountain for 

 some hours, generally not before 11 a.m. or noon. Before that time, 

 however, masses of mist have been rolling over Dorjiling ridge to the 

 westward, and gradually filling up the valleys, so that by noon, or 

 1 p.m., every object is in cloud. Towards sunset it falls calm, when 

 the mist rises, first from Sinchul, or if a south-east wind sets in, from 

 Tonglo first. 



The temperature is more uniform at Mr. Hodgson's bungalow, 

 which is on the top of the Dorjiling ridge, than on either of its flanks ; 

 this is very much because a good deal of wood is left upon it, 

 whose cool foliage attracts and condenses the mists. Its mean 

 temperature is lower by nearly 2|° than that of Mr. Muller's and 

 Dr. Campbell's houses, both situated on the slopes, 400 feet below. 

 This I ascertained by numerous comparative observations of the 

 temperature of the air, and by burying thermometers in the earth : 



* This is a most important point, generally wholly neglected in India, where I 

 have usually seen the thermometer hung in good shade, but exposed to reflected 

 heat from walls, gravel walks, or dry earth. I am accustomed from experience to 

 view all extreme temperatures with great suspicion, on this and other accounts. 

 It is very seldom that the temperature of the free shaded air rises much above 

 100°, except during hot winds, when the lower stratum only of atmosphere (often 

 loaded with hot particles of sand), sweeps over the surface of a soil scorched by 

 the direct rays of the sun. 



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