AND METEOROLOGY OF DUKHUN. 195 



29th of April, the 9th, 11th, and 12th of May 1829, on the hill fort of Hurreechun- 

 durghur. 



I made some observations on solar and terrestrial radiation in 1828 and 1829, 

 and had purposed extending them through several months ; but unfortunately the 

 severe labour of my statistical duties in those years did not admit of my devoting 

 the necessary time to the interesting inquiry. In 1830, however, I persisted in in- 

 vestigating the subject day and night during the whole year, but as this paper is 

 already too voluminous, I must reserve the details for a future communication. I 

 will simply remark, that a thermometer on the grass covered with black wool at 

 2 P.M. on the 25th of November 1828, at Poona, rose to 164° Fahr., whilst a thermo- 

 meter in my library stood at 7Q°'Q\ the force of the solar power, therefore, was 87°-4, 

 far exceeding the maximum of any observations that have come under my notice : 

 and I find that grass was frequently exposed to a range of more than 111° Fahr. be- 

 tween sunrise and 2^ 30™ p.m. 



The opacity of the atmosphere in the hot months is very remarkable. In looking 

 from the crest of the Ghats over the Konkun at sunrise, the sky would be free from 

 a cloud, and every object in the Konkun 3000 or 4000 feet below the spectator di- 

 stinctly visible in the intervals of the fogs previously noticed : as the day advanced 

 and the heat increased, the air would get misty, but without a cloud in the sky, and 

 by 1 or 2 o'clock objects of great magnitude only would be visible in the Konkun, 

 seen as through a diaphanous medium. The upper surface of this stratum of hot air 

 was horizontal and quite defined. I found it very rarely reach to the height of 4000 

 feet, and I could invariably foretell the temperature of the coming afternoon above the 

 Ghats, by observing at 9 or 10 a.m. the height of the upper line of the heated atmo- 

 sphere of the Konkun. If very high at those hours, compared with the preceding 

 day, the temperature would be high ; and vice versa. In the Desh or open country 

 above the Ghats, the heated air rises for a few feet from the ground in wavy lines ; 

 and objects seen through the atmosphere in this state have an undulatory flickering 

 motion. 



Humboldt most truly says, that in judging of temperature, nothing is more deceit- 

 ful than the testimony of the senses : we can judge of the diff*erence of climates only 

 by numerical calculations. Having felt the full force of this dictum, I have thought 

 it necessary to expatiate fully on the meteorology of Dukhun ; and it now only re- 

 mains for me to show how far the preceding numerical indications are coincident 

 with salubrity of climate. This point I shall illustrate by a few facts equally brief 

 and satisfactory. I was six years and one month in Dukhun employed in my sta- 

 tistical labours : my followers in the field, with their famihes, always exceeded one 

 hundred persons, and in monsoon quarters the number was rarely below forty. 

 During the whole period, and amongst such a number of persons, there was not a 

 single casualty of an adult, and only one of an infant shortly after its birth ; and but 

 one case of disease that I could not cure myself without professional aid, — a degree 

 of healthiness which probably few other countries can equal. Dr. Walker, long civil- 



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