during the Quarter ending March 31, 1849. 367 



The interval of time between January 8 and March 17 was 

 distinguished by very unusual warmth for the season. The 

 average daily excess of temperature within this period was 

 6°'l ; on four of the days this exceeded 12°, on three days it 

 exceeded 13°, and on two days it was greater than 14°. 



The mean temperature of the three montiis ending Febru- 

 ary, constituting, in fact, the three winter months, was 42°*5, 

 being no less than 4°*7 above the average temperature of the 

 same time for seventy years. The warmest winters within this 

 period were those ending February 1796, 1822, 1834 and 1846, 

 and which were 43°-2, 42°-4, 43°-0 and 43°-2 respectively. 



The pressure of the atmosphere during the month of Fe- 

 bruary was very unusual. The average reading of the baro- 

 meter from the 1st of February till the 18th was 30*36 inches 

 at the height of 160 feet: this was fully half an inch above its 

 average value. This denotes an increase in the volume of air 

 of about one- sixtieth part above the usual quantity. On the 

 11th day the very unusual reading of 30-715 inches took 

 place. The true reading for the whole day, reduced and cor- 

 rected to 32° Fahrenheit, was 30*695 inches, showing that 

 about one-thirtieth more than the usual quantity of air was 

 over England on this day. The reading of the barometer on 

 the 1 Ith day, reduced to the level of the sea, was 30'91 inches. 

 In December 1778 the reduced reading was 30*90 inches; 

 in January 1825 it was 30*92 inches ±. 



The condition of the atmosphere, therefore, during the 

 greater part of the past quarter, both with respect to pressure 

 and heat, has been very unusual. 



From the discussion of the observations which have been 

 made at the Apartments of the Royal Society since 1774, there 

 appears to be no foundation for the opinion that a hot summer 

 either precedes or follows a cold winter ; on the contrary, the 

 hot summers have for the most part been accompanied by 

 warm winters. 



From the long continuance of high temperatures, it would 

 seem that for some time past causes have been in operation 

 which have raised the temperature: these causes probably 

 still exist, and therefore there seems to be every probability 

 of a fine and warm summer. 



I proceed now to detail the results of the several subjects ol 

 research in the past quarter. 



The meaji temperature of the air — 



For the month of January was 40°*1, exceeding \he average 

 of seventy years by 4°'3. The temperatures in this month in 

 the years 1775, 1796, 1804, 1806, 1819 and 1834, were those 

 only which exceeded that of this year. In the year 1796 it 

 was 45°'4p being the warmest on record ; 



