during the Quarter ending September 30, 1849. 359 



their average values ; the mean deficiency was 2°*2. From 

 August 6 to August 12 the temperature was high; its mean 

 daily excess was e'^'O. From August 13 to August 19 the 

 mean deficiency was 1°'9. From August 20 to September 15 

 the temperature was high ; its mean excess was 4° ; and this 

 period was distinguished by a thick and stagnant atmosphere, 

 and the air was for the most part very close and oppressive. 

 The temperature was 3°*3 below its average from September 1 1 

 to September 21 ; and it was 5°' 5 in excess from September 22 

 to the end of the quarter. The summer has been warm and 

 dry, without great heat. Thunder-storms have been very 

 frequent during the quarter. The air has been for the most 

 part unusually dry. The amount of rain has been less than 

 usual in latitudes south of 53°, and north of this parallel it 

 has been greater. The magnets have been seldom disturbed 

 during the quarter ; and the amount of electricity, though less 

 than usual, seems to have been so in consequence of the less 

 amount of humidity of the air. 



The weather has been much finer in the southern than in 

 the northern parts of the country. 



The mean temperature of the three months ending August, 

 constituting the three summer months, was 61°'0; and that 

 of the average of seventy summers is 60°*0. 



The several subjects of research in the past quarter are as 

 follows : — 



The mean temperature of the air"^ for the month of July was 

 62°-l, which is 4°-3, l°-9, l°-2, 0°-7, 2°'3 and 0°-6 afiot;^ those of 

 the years 1841, 1842, 1843, 1844, 1845 and 1848 respectively; 

 and is 2°'4 and 3°'3 below those of the years 1846 and 1847 

 respectively. The temperature of this month exceeded its 

 average from seventy years by 0°*7. 



For the month of August was 62°- 9, which is 2°-4, 0°-8, 

 5°-2, 5°'6i 0°-8 and 4°-4 above those of the years 1841, 1843, 

 1844, 1845, 1847 and 1848 respectively; and is 2°-5 and 0°-3 

 below those of the years 1842 and 1846 respectively. The 

 temperature of this month exceeded its average from seventy 

 years by 2°*1. 



For the month of September was 58°'8, which is 0°*7, 2°'4, 

 1°'9, 5°'2, 4°"5 and 3°'0 above those of the same month in the 

 years 1841, 1842, 1844, 1845, 1847 and 1848 respectively; 

 and is 0°-7 and l°-3 below that in 1843 and 1846. The 

 temperature of this month exceeded that of the same month 

 on an average of seventy years by 2°*1. 



* For the monthly, quarterly and yearly mean temperature of the air 

 from 1786 to 1843, see my paper in the Philosophical Transactions, partii. 

 1 849 ; and for the mean monthly values of several meteorological elements, 

 see my paper on Meteorology in the Illustrated London Almanac for 1850, 



