SURVEY OF THE EAST OF FRANCE. 
15 
Table VII. 
Station. 
H. F. 
V.F. 
T. F. 
m. 
Vaugirard 
4-1232 
9-1840 
10-0672 
0-47388 
Rlieiins 
4-1198 
9-2113 
10-0907 
0-47304 
Metz 
4-1570 
9-0904 
9 9958 
0-47342 
Strasburg 
4-2531 
8-9782 
9-9346 
0-47375 
Ivsenheirn 
4-2743 
8-9883 
9-9328 
0-47393 
Mont Roliand 
4-3325 
8-9719 
9-9632 
0-47361 
Dole 
4-3231 
8-9341 
99251 
0-47365 
Dijon 
4-2974 
8-9586 
9-9361 
0-47339 
Lyons 
4-4488 
8-8195 
9-8780 
0-47364 
Avignon 
4-6254 
8-6282 
9-7897 
0-47371 
Marseilles 
4-7238 
8-3629 
9-6048 
0-47378 
Monaco 
4-6602 
8-5233 
9-7142 
0-47341 
Montpellier 
4-6389 
8-5713 
9-7461 
0-47391 
Grenoble 
4-4348 
8-6554 
9-7252 
0-47358 
N. D. de Myans 
4-4847 
8-7403 
9-8236 
0-47304 
Mongre 
4-4143 
8-8385 
9-8796 
0-47314 
St. Etienne 
4-4641 
8-7711 
9-8417 
0-47321 
Clermont 
4-4044 
8-8613 
9-8956 
0-47343 
Moulins 
4-3387 
8-9135 
9-9134 
0-47346 
Vaugirard 
4-1132 
9-1619 
10-0429 
0-47377 
Douay 
3-9964 
9-3003 
10-1226 
0-47315 
Boulogne 
3-9491 
9-3428 
10-1431 
0-47352 
These values of H. F., combined with the second members of our previous set of equa- 
tions, which remain unchanged, will give us the equations of condition for determining 
the lines of equal Horizontal Intensity. Reducing these equations by the method of 
least squares, we obtain : — 
27-3408=: 20 A— 2521 #+ 3057 y, 
-3560-9763= -2521 A +42141 3 #-447498^, 
4782-1935 = 3057 /?.— 447498 #+910595 y; 
.-. A=II. F. — 3=1-1259, 
#= — 0-000317, 
y= 0-001316. 
Hence r=0 - 00135, or the lines whose IT. F. differs by 0-1 are 73-7 miles apart; and 
u= — 76° 27' 16"-5, or the direction of the lines is N. 76° 27' 16" - 5 E. to S. 76° 27' 16"-5 W. 
A substitution of these values in our original equations will enable us to form a Table 
of the computed Horizontal Force for each station. 
