BAROMETRICAL MEASUREMENT OF HEIGHTS. 



Example 1. 



Suppose to be given, 



B = 333.6 Paris lines ; T = + 17.0 Reaumur ; t = + 19.0 R. ; <j> = 48. 

 B' = 289.9 Paris lines ; T' = + I6.3 Reaumur ; f = -f 15.2 R. 

 T T' = 0.7 t + t' = + 34.2 



r = + 8.55 



In Table II. with B take H = 864.9 

 with B' take H' = 291.2 



H H' = 573.7 H i^ = 6 - 737 



H H' T-+8.55 



"IOC *' = 49 ' 6 II? 



u = 622.06 10 



In Table III., with u and T, take C = +1.8 

 In Table IV., with u and <, take C' = 0.2 

 In Table V., with T T' and r take C" = 0.0 



Difference of elevation, or h = 623.66 toises. 



Gauss's Tables give 623.64 toises. 



Example 2. 



Suppose to be given, 



b = 342.68 Paris lines ; t = 10.38 Reaumur ; < = 65. 

 I' = 285.47 Paris lines ; t' = 14.94 Reaumur; T T' = 0. R. 

 t -f t 1 = 25.32 

 T = 6.33 



In Table II. with I take H = 974.58 

 " with V take H' = 228.28 



H H' = 746.30 H ^, H '= 74 63 



H H' T = 6.33 



-loo- * - ~ 47 ' 24 12 



= 699.06 H-H' 



In Table III., with u and T, take C = + 1.8 10 



In Table IV., with u and <, take C 7 = 1.2 



A= 699.66 



Gauss's Tables give A = 699.72 toises. 



63 



