Meteorological Obfervations. 535 
Mean height of the Barometer at Liverpool 
in each month, deduced from an average of 
twenty-five years. ‘ 
January |29,71|May 1|29,80|September| 29,69 
February|29,58|June |29,82/October | 29,71 
March }29,80}jJuly }29,82| November} 29,64 
| April 29,73 | Auguft | 29,81 | December | 29,64 
It is evident from this ftatement, that the 
mean height of the barometer is greater during 
the months of May, June, July, and Auguft, than 
in any other four months. And this does not 
depend upon the expanfion of the mercury by 
heat, independent of its weight : for the difference 
in the expanfion of the mercury from this caufe, 
‘between the greateft cold of winter and heat of 
fummer, never exceeds ,03 of an inch. 
Obfervations on the Barometer at Dover, extrafted 
from a ‘fournal kept by Mr. T. Mawnrett, 
Surgeon at Dover. 
The obfervations commence in Oétober 1 789. 
17 89 c Mean. Higheft. Loweft. 
‘October | 29,61 30,21 28,74 
November 29,64 30,42 28,60 
December 29,81 30,48 29,10 | 
1790. 
