

Of BAROMETRICAL MEASUREMENTS. in 



or c _ 



' H ' Q 



(s+x) (i m) 



26. IN the cafes which actually take place in nature, v is 

 either equal to + 2, or to I. It is equal to + 2, when the 

 barometer is raifed above the furface of the earth, and to r, 

 when it is depreffed below it. When * = + 2, the laft equa- 

 tion becomes 



n Ztt t 2 



.q (j+y) (l m} nt_/- x ___ 



in n n I 2 ?vw 



/ ft - ( J+ *)(i m) 



When x is fuppofed very fmall in comparifon of s, the fluent 

 f -- 2 - A* ma y ^ e ex P reu " e( i by a feries, converging with 



^ 0+*) (I OT) 



fuch rapidity, that the two firft terms will be fufficient for the 



prefent purpofe. Now, as 



2 



I / 2* N . ns 2 & 



[i -- ) nearly, / - - - becomes 

 s 2 t s J J q / * x 



(i ffz) 



_ n , _ *x 2 ^\ " / I 2* 2 \ 



/ (l m) x (i ) ~ ( ). 



?/ V s' **\ *S *P ^V 



? C 1 m ) 



n 



Therefore, -^i 



)' To define C, muft be put 



:= o, 



