1839] 



0?i the Statistics of Dukhun. 



153 



moisture, greater prevalence of westerly winds, a more limited range of 

 the thermometer ; but a greater prevalence of fogs before, during, and 

 after the rains, but not in the winter months ; and, finally, is characte- 

 rized by the absence of hot winds. The Desh, on the contrary, has the 

 air excessively dry in the hot months ; a great diuinal and annual range 

 of the thermometer, a comparatively small fall of rain in the monsoon, 

 the frequent occurrence of hot winds, and the rareness of fogs. 



Barometer. — The mean monthly pressure of the atmosphere is great- 

 est in the winter months of December and January ; it gradually dimi- 

 nishes until July or August, the most damp months, when it is at its 

 minimum; it gradually increases again until the cold months. The 

 greatest diurnal oscillation recorded by me in several years' observations 

 was '1950, or less than two-tenths of an inch ; the smallest oscillation 

 •0150. The mean rise of the barometer from sunrise to 9 — 10 a. m. for 

 three years was -0445, thermometer -t 7°-15''. The mean fall from 9 — 10 

 A. to 4 — 5 p. M., for four years, was -1066, thermometer -\ 5'^*21' ; 

 and the mean rise from 4 — 5 a. m. to 10 — II p. m., for one year, is *0884, 

 thermometer — 7° -2'. The maximum range of the barometer at Poona, 

 in the year 1880, at 1823 feet above the sea, was only -672, or not seven- 

 tenlhs of an inch. The mean height of the barometer for that year was 

 27°-9254, and the mean height in the monsoon was 27 ° "8447 ; so that 

 the constant moisture of the monsoon only occasioned a mean diminuti- 

 on of pressure of -0807? or less than one-tenth of an inch. At Madras^ 

 for twenty-one years, the mean height of the barometer was 29®-958' 

 inches ; at Calcutta, the means of three years make it 29-764. M. Arago, 

 at Paris, by nine years' observations, reduced to the level of the sea^ 

 makes the mean height 29-9546 inches, being almost identical with the 

 mean height at Madras. 



Almosplier'ic tides. — There are four tides of the atmosphere in Dukhun, 

 as indicated by the movement of the barometer ; two diurnal, and two 

 nocturnal : the diurnal rising tide is from 4 — 5 a. m. to 9—10 a. m., and 

 varies from -0200 inches to -0500 inches; the falling tide is from 9—10 

 a. M. to 4—5 p. M., and varies from -1950 inches to '0150 inches. The 

 nocturnal rising tide is from 4 — 5 p. m. to 10 — 11 p. m., and varies from 

 •0450 inches to -1 140 inches ; the nocturnal falling tide is from 10 — 11 

 p. M. to 4—5 A. M., and is about -0442 inches, This order was never de- 

 ranged or inverted in one single instance in many thousand observations. 



Temperature, — The climate of Dukhun is subject to very considerable 

 variations of temperature; more, however, in the diurnal than in the 

 monthly or annual ranges ; indeed, less so in the last particular than in 

 Euro];)e* In 1827, the extreme range of the thermometer at Edmonton 



