Ixvi GENERAL RESULTS OF THE MAKERSTOUN OBSERVATIONS. 
lowing quantities, the means for groups of days from four years’ observations, are obtained from the last column 
of the first parts of Tables 28 and 45. (Prefix 0:000.) 
Moon’s Age, 14a_16¢ 174204 214244 — 95a__Ba 29414 2454 6h—ga 104134 
Variations, — 024 + 007 + 024 + 011 + 001 + 008 + 009 — 034 
The total force, therefore, is least near opposition, and it is greatest near the quadratures. (See No. 96, 1st.) 
140. Variations of the Daily Mean Total Magnetic Force, with Reference to the Moon’s Declination — 
The following variations are derived from the final columns of Tables 28 and 45. (Prefix 0-000.) 
pte Ree GUS 215d 6A—84 Qd_jod = ygd_154 = 164194 BOA_99a Baga 
Variations, + 024 — 004 —016 — 010 + 017 — 004 — 001 —005 
These variations indicate that the total force is a maximum when the moon is farthest north, and also 
when it is farthest south, and that is a mimimum between these epochs. This result is quite analogous to 
that for the sun’s position in declination (see No. 136). In both cases, the total force is greatest when the body 
(sun or moon) has its greatest north and south declinations, and it is least during the intermediate positions, 
or when the body is near the equator. 
141. Monthly Variations of the Range of the Total Force.—This law is the same as that for the vertical 
component (No. 97), but has not been deduced for the total force, for the reason given No. 127. It may be 
stated gener; ally, whether the position of the sun or the moon be under Coneiieer cnn that the diurnal range of 
all the magnetic elements is greatest when the body is rather north of the equator, and that the range is least when 
the body is farthest south and farthest north. It has been found, generally, that when undisturbed mean 
variations are examined, the diminution of diurnal range, when the sun is most northerly, disappears, and 
it is probable that the same would be true with respect to the moon; the excess of range, when the bodies 
are near the equator, being due to the greater amounts of disturbance which occur at these times. 
(See No. 23.) 
TABLE 62.—Diurnal Variations of the Total Magnetic Force for each Month, as deduced from the 
Regular Daily Observations made during the Four Years 1843 to 1846. 
mOOCnNAUtrwne oOo 
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