1303 
h = (&—e,) b, 4 — sin’ p). 
Taking Z, == 0.0179 r,, and A, = 2.70, and integrating over the 
whole surface we find for this part of H—H,, using also (4): 
dB = 0.023 (e—e,) — 0.012(H—H,) . . . . (%) 
The principal part of H—H, is due to the deviation of the actual 
surface from the normal surface. This has been computed by (5’) 
and (6), replacing 4, and d, by 4 and d respectively. The value 
of the constant g depends on Z and on the units used. | have 
adopted. A:== 2.70, 2! = 1.70"), Z= 114-km. 
The surface of the earth was divided into compartments of about 
100 square degrees. For each compartment the value of 
Q = qu (a,h — 0.57 ed). 
was computed, where a, and «, are the fractions of the compart- 
ment covered by land and by sea respectively (so that «¢, + «, = 1). 
Further 
P= Q(1—8 sin? p) 
R= Q cos? p cos 2A 
S= Q cos* op, sin 22. 
The units had been so chosen that 
20-—A—B Beit 
dl EP 
2C 
ae is SS ain | 
J G = 10-7 (2K. cos 2a, + 2S. sm 2A,}, 
The longitude 2, is determined by 
=S cos 24, — {RK sin 24, — 0. 
1 found the following results. (See table p. 1304). 
We ‘find thus 
2C0—A—B 
Se ae 
2C 
BoA | 
8 = + 0.00000205, 
and the axis of minimum moment of inertia (4) is situated in the 
longitude 
4, = 86.°5 West of Greenwich. 
This computation, of course, is rather rough. It would perhaps 
be worth while to repeat it with greater care. The small influence 
of the continents, especially of Asia, is somewhat surprising. This 
1) The normal density of the crust in the upper few kilometers be/ow the 
normal surface was thus taken to be 2.73, and the density of the land projecting 
above that surface 2.70. 
