550 Sir george shuckburgh’s Obfervations 
+,ooi, equal to about io inches in deducing the height 
of the mountain, a quantity wholly to be negledted. 
Finally, the mean of Mr. de saussure’s obfervations 
gives the defe6t of Mr. de luc’s rules 21.9 in a thou- 
fand. The conftrudtion of the barometer had therefore 
no influence on this difference. But further, while Mr. 
de saussure obferved the height of the barometer on 
the Mole, Mr. de luc, the brother made a correfponding 
obfervation with a fimilar inftrument at Geneva. I ill all 
relate this obfervation, computed after Mr. de luc’s 
manner. 
Mr. 
