MAGNETIC INEQUALITY AT HOBAETON. 
Direct Solar-diurnal Variation . — Table II, exhibits the mean solar-diurnal variation 
for the same four periods, each of two years’ duration, derived from the observations after 
the exclusion of the larger distm-bances. The sign + signifies Easterly and — Westerly 
difierences fr'om the mean or normal direction in the twenty-four hours. 
Table II. 
Hours. 
1841 
and 
1842. 
1843 
and 
1844. 
1845 
and 
1846. 
1847 
and 
1848. 
Hours. 
1841 
and 
1842. 
1843 
and 
1844. 
1845 
and 
1846. 
1847 
and 
1848. 
Noon. 
+ 1-61 
4 - 1*29 
+ 1*20 
+ 1*00 
12 
- i*oi 
- 6*87 
- 1*04 
-6*89 
1 
+ 3-46 
- f 3*19 
+ 3*42 
+ 3*79 
13 
- 0*77 
- 0*68 
- 0*86 
- 0*65 
2 
+ 4*42 
44*03 
+ 4*54 
+ 5*25 
14 
— 0*56 
- 0*41 
- 0*62 
- 0*49 
3 
4 - 4*10 
- 43*85 
+ 4*46 
+ 5*01 
15 
- 0*33 
- 0*26 
— 0*42 
- 0*36 
4 
+ 3*04 
- 42*96 
+ 3*44 
+ 3*83 
16 
— 0*41 
- 0*33 
- 0*46 
— 0*43 
5 
-f 1*82 
41-82 
+ 2*08 
+ 2*23 
17 
- 0*76 
- 0*59 
- 0*86 
- 0*95 
6 
+ 0*99 
40*98 
+ 1*11 
+ 1-37 
18 
— 1*30 
- 1*07 
— 1*26 
- 1*40 
7 
+ 0*36 
+ 0*40 
+ 0*46 
+ 0*80 
19 
— 2*13 
— 1*85 
- 1*83 
— 2*53 
8 
— 0*16 
- 0*11 
- 0*07 
+ 0*27 
20 
— 3*04 
- 2*88 
— 3*00 
— 3*74 
9 
- 0*72 
- 0*55 
— 0*52 
- 0*25 
21 
— 3*36 
- 3*29 
— 3*61 
— 4*51 
10 
— 1*03 
- 0*92 
- 0*91 
- 0*64 
22 
- 2*46 
- 2*71 
- 2*92 
- 3*92 
11 
— 1*11 
- 0*95 
- 1*09 
- 0*90 
23 
- 0*63 
- 0*98 
- 1*19 
- 1*91 
In all the four periods the greatest easterly deflection occurs at 2 p.m., and the greatest 
westerly at 9 a.m. The extreme difierences are, — 
2 P.M. Easterly . . 
9 A.M. Westerly . . 
Sums 
1841 — 1842 . 
. 4-42 
. 3-36 
. 7-78 
1843 — 1844 . 
4-03 
3-29 
7-32 
1845 — 1846 . 
4-54 
3-61 
1847 — 1848 . 
5-25 
4-51 
9-76 
Here also, if we estimate the decennial variation by the difference in the range of the 
dim-nal movement, we find 1843 — 1844 the years of minimum and 1847 — 1848 those 
of maximum ; although the inequahty between the extremes is not so great as in the 
distm’bance-variation. 
We obtain this result from the eight years in which the observations were made hourly ; 
but we have also observations in the six following years made with the same instruments 
at the hour’s of 2 p.m. and 6 A.M., and we are thus enabled to trace the decennial inequality 
through a period of fourteen consecutive years. In so doing we have to employ 
throughout {i. e. in the eight years as in the six years) the mean positions at 2 p.m. and 
6 A.M. only. The range in the different years is here strictly comparative, but it is not of 
course the extreme range. Table III. shows these particulars. 
