262 REPORT—1896. 
desirable to show side by side the results for all the elements throughout 
the same series of years. 
There are five selected ‘ quiet’ days a month, and so a total of 360 in 
the seventy-two months of the six years considered. In November 
and December 1890, however, the vertical force magnetograph was out 
of action, which reduces by ten the number of days available in the case 
of the vertical force and inclination. 
In the following table, I., the six Januarys, six Februarys, &e., of the 
six years have been combined together, so as to show the values of the 
cyclic effects at different seasons of the year. The figures under the 
heading ‘Individual Months’ show in how many of the six Januarys, &c., 
the effect was an increase of the element in question, was nil, or a decrease. 
At the foot of the table appear the mean non-cyclic effects per ‘ quiet’ 
day throughout the six years, and the totals of the several columns under 
the headings ‘ Individual Months.’ 
Taste I.—WNon-cyclic Effect from Six Years, 1890-1895 (Mean per 
‘Quiet’ Day). 
DECLINATION HORIZONTAL FORCE VERTICAL FORCE INCLINATION 
Month | rm ry 7 ln ial 
| Individual| (Effect) | Individual | (Effect) | Individual | ;, Individual 
Effect Months : x 10° } Months x 10° Months Effect Months 
| | 
+0 -— a Oh | +0— | +0-— 
January . | +0°63 | 6 +50 5 1 —52 6 | —0"47 | 1 5 
February. | + -33| 4 2 +57 i al +5 3 eal eae eal 5 
March | + *18) 3 3 +28 bial +13 22" 2 — ‘17 I wily 4 
April SA 8 Le +20 4.14 1 —22 2 4 — 20 3 [es (et 
| May . «|?+ °07 3 3 +38 5 1 —12 3 3 — ‘27 2 4 
June. - 17 3 3 +22 2b: —28 1 5 | — "22 te 
| July . — 23 | 3 3 +27 4.2 —13 1 5 — +22 2 4 
| August — 30/ 11 4 +37 5 1 — 8 3 3 — 27 by 
September | + 12 3 3 +38 6 +30 Diet ast — 18 5 
October + °03 2 Lie +50 6 + 5 3 3 — "28 1 5 
November | + °18| 3 1 2 +53 6 —12 2 3 — 40 5 
December. | — ‘10| 1 2 3 +15 5 1 — 6 2 3 — 12 2 3 
Annual } 
mean . | +0/072 - +36°4 — =8'3 = | —0/-263/ - 
| | 
Totals of | 
months. — 35 6 31 — 60 7 5 — 25 3 42 — 9 8 53 
In the case of the declination + signifies a deflection to the west. The true secular variation at 
present is towards the east. The components of force are measured in C.G.8. units. 
Table II. gives the mean results for the several quarters of the year as 
deduced from Table I., while Table III. gives the annual means for the 
individual years. 
TasiE II.—Mean Non-cyclic Effect per ‘ Quiet’ Day for each Quarter 
of the Year. 
_— Declination ec Force) (Vertical Force) x 10° Inclination 
Quarters] 1 AD INE 2 RE Bei Pe 4) ee 
+3 | —4 |-0-33| —-23| —-g2' —-28 
Effect. .| +038) +-01 —-14) +04) +45) +27/ +34 | +39 | cate 
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