19 



A Table of the greatest and least observed heights of the 

 Barometer for the last thirty-eight yearSj taken at 

 Greenwich, and reduced to 32 of Fahrenheit. 



In the preceding table the maximum elevation for the 

 period of thirty-eight years occurred in 1825, when the 

 mercury stood at 30 '89 inches; in 1821 it however 

 reached 30-82 inches; in 1835, 30-84 inches; and in 

 February 1849, 30-86 inches. It is recorded that Sir 

 George Shuckburgh, in 1778 in London, observed the 

 barometer at 30*935 inches, which he believed to be the 

 greatest elevation ever seen. 



In the extreme depressions, those of 1821 and 1843 



