124 P. E. Chase on Terrestrial 
Table I is compiled from Maj. Gen. Sabine’s Tables 86, 31, 
50, 51, 52, 53 (St. Helena Observations, ii). It is especially im 
teresting as showing the influence of the opposition of attrae 
tion to rotation in producing low solar tides at 10 or 11 a 
the prompt and direct influence of the sun upon the ethereal 
currents in the production of a high tide at noon, the dounle 
maxima and minima in each of the lunar tides, the additional 
confirmation of the analogies that I have heretofore pointed out 
between the spheroids of attraction and rotation, the o position 
of the solar and the resemblance of the lunar zenith and nadir 
effects, and the evidence in the partial ‘“ establishment” of the 
rectly on the xether, through the intervention of atmospheric at 
traction-currents, 
Tables If and III were formed by taking the. mean of the - 
hourly averages, on the twenty-four days in each lunar month 
which are most nearly indicated by the angular positions givél 
in the first column. Each of the tabular numbers for 1844 and 
1845 represents the average of two hundred and eighty-eight : 
hourly observations; each of the numbers for 1846, the aver 
age of two hundred and sixty-four observations, with the few : 
exceptions of holidays and other omitted days, for which the 
missing numbers were interpolated. Table II indicates a tend 
ency to mean lunar influence between 90° and 105°, and ie 
tween 270° and 285°, the influence increasing when the moon — 
acts either in conjunction with the sun, or directly upon coh | 
Taste IIT. 
Lunar-Monthly Magnetic Tide of Vertical Force. 
Monts Mean Daily Fluctuations of Vertical | Mean Daily Fluctuations of Vertical) 
ee 2.6 
F : Force 3 he Moon’. - 63 ese. 
Positive. _ ae — acs | sar ie Porce at »t. Hele ae : 
° ts Hiteodll thtoadl Fo rs 1844. | 1845. | 1846. | average. 
O | 4842/4851 43-56) 4683 || 180 | 47-06 | 4777 | 46°54 Nd 
15 | 4821/4855 4390 | 46-89 195 | 4796 | 48-02 | 46-99 | 474° 
80 | 4733 | 4853 4453 46-80 210 | 4814 | 48°26 | 45°63 | 4748 
: 3 
0 | 47:55 | 4750 | 47-9: | 
Legh 147821 4770 4702! 47-41 || 3845 | 49-18 | 47-44 | 4399 
densed air and vice versd. It also shows the existence of distur 
ances, which may be accounted for by some of the causes 
which I have already referred. Table III exhibits apparent 
‘tendencies to diminution of force near the syzygies, and tol 
crease of force a day or two after the quadratures, 
* The value of le division varies from “00051 to -00091 of the vertical for 
