114 Prof. E. Hull—Continental Lands and Oceans. 
this conclusion corresponded with actual observations on the length 
of the second’s pendulum at stations all over the globe as tabulated 
by Airy.’ The formula of Suess and Fischer based on these was to 
the effect that the difference in the level of the ocean between two 
such stations was found in métres by multiplying the difference in 
the number of daily oscillations in the second’s pendulum by 122. 
This in the case of the stations of California (or Mexico ?) in lat. 
21° 30’ and of the Sandwich Islands would amount to 4520 feet: 
a very startling result if correct. 
The author proceeded to discuss the effect of continental lands, 
showing that this was in the first instance divisible under two 
principal heads: The effect (1) of the unsubmerged, and (2) of the 
submerged masses. In the former case (i.e. where the mass rose above 
the surface), one component of the attraction acted in a more or less 
vertical direction ; in the second case, all in a lateral direction ; but 
both had the effect of elevating the surface of the ocean. The 
horizontal distance to which the vertical effect extended owing to 
the curvature of the earth’s surface was then considered ; and it was 
shown that, where continental lands rise from a deep ocean, the 
effect of the lateral attraction far exceeds that of the vertical attrac- 
tion of the unsubmerged mass. Professor Stokes had furnished the 
author with a hypothetical case, in which the elevation of the ocean 
was estimated to reach 400 feet above the mean geodetic surface of 
the earth. 
For the purposes of illustration three cases were selected, viz. :— 
(1) The table-land of Mexico, between lats. 18° and 26° N. 
(2) The table-land of Bolivia, us 19° and 26° S. 
(3) The Andes of Chile, i 26° and 35° 8. 
The mean elevations, distances from the ocean, and extent having 
been determined, and the mean density of the crust being taken at 
2°6 for emergent, and 1:6 for submerged, land, the results of the 
attraction of the mountain masses in each case were as follows :— 
(1) Mexico, 280 feet; (2) Bolivia, 301 feet; (8) Chile, 63 feet; 
the elevations being calculated above a mean geodetic surface. 
To the above results, due to the gravitation-potential of the 
elevated masses, were to be added those due to the following 
factors :— 
(a) The marginal plain or emergent tract on either side of the mountain mass. 
(2) The high lands both to the north and south of the special sections above 
dealt with. 
(c) And lastly, and most important, the submerged continental mass. 
To provide for the sphericity of the earth deductions of various 
amounts, according to circumstances, were made from the numbers 
obtained from the formula which Mr. Close had arrived at by a 
double process, and which is given at length in the paper itself. 
Combining these results with those given above, we obtain as the 
whole rise of the ocean surface as follows :— 
(1) Mexico, 780 feet ; (2) Bolivia, 2159.feet; (3) Chile, 1582 feet. 
In all the above cases the coast was taken as descending to a 
1 Airy, “On the Figure of the Earth,’’ Bncyclop. Metropolitana. 
