APPENDIX. XI 



I hope next year with Capt. Herbert's assistance to deduce the altitude of Suha- 

 ranpoor from a more accurate series. 



While upon the subject of the Barometer I should mention that Adie's Sympiesa- 

 meter was also registered, and for sometime it agreed very well, but at the end of the 

 first year the bulk of air above the oil was found increased in quantity 3-lOths and 

 after the second year 2-10ths of an inch so that no dependence could be placed upon 

 its readings, except for a short period. 



TEMPERATURE. 



The several Thermometers used by me were compared with a Standard Instru- 

 ment made by Dollond, and divided to fifths of a degree. The external ones were si- 

 tuated in a northern veranda perhaps hardly sufficiently exposed to the air, but en- 

 tirely sheltered from the sun's rays. The in-door ones were in a northern apartment 

 closed during the day and without tatties. As the observations were made five times 

 a day including the extremes noted by the self-registering thermometer, I was able 

 to construct for each month a curve whose ordinates expressed the temperature for 

 each half hour of the day; the means of these are denoted in the 10th column under 

 the title " Mean of the twenty-four hours ;" they differ little from the morning and even- 

 ing means. 



From the whole mass of observations the temperature of the air is found to be 

 77 degrees, being 3 degrees lower than the mean heat of a well 36 feet deep which 

 was found in August, 1822, 80° 95' 



December, 78 20 



April, 1823, 80 50 



December, 80 00 



79 91 



In the close streets of the city, where the heat is not so easily dissipated as at 

 Secrole, a diary kept by my pundit gives a mean result of 79° 22'. 



All of these contradict the formula of Mayer which ascribes only a mean tempera- 

 ture of 74° T (— 1° for an altitude of 300 feet above the sea) = 73° 7' for the latitude 

 oi'Eenares 25° 211 



In the month of May for several clays the thermometer rose to 111 5'and in Janu- 

 ary it fell at night to -15° including a range of QG degrees. 



