Ixxx 
General Results of the Makerstoun Observations. 
1849. 
Feb. 
Gott. M. ' 
d. h. 
19 8 
9 
10 
Fig:2\ 
rw 
40™. Homogeneous auroral bank to X. with slight appearance of an arch. 
S^^-SS™. Magnificent bow of aurora passing between Castor and Pollux, as in Fig. 1 ; shortly 
afterwards a series of waves 
seemed to move along the 
lower edge of the bow from 
east to west, and in a di- 
rection opposite to the very 
violent wind then blowing 
from west; the appearance 
of the waves is shewn in 
Fig. 2. 
10"". The source of the waves 
was observed as in Fig. 3 ; the 
bow was seen to be at the base 
of a series of beams, which 
converged to the anti-dijJ ; 
the beams were but faintly 
visible, but they were observ- Fig: 3 
ed to rotate about the point c, 
the centre of the corona, the 
beam a, appearing to occupy 
successive positions, till it 
arrived at the position h ; in this rotation the wave-like motion observed in Fig. 2, was produced. 
The sky was quite clear, and the wind blowing very violently. It is not a little curious that on the 
following evening, Feb. 20th, Professor Forbes observed a similar arch in almost the same position. 
He has obliged me with the following note of his observation : — 
" Edinburgh, 20th February 1849. — At 10'^ 10", p.m. [Greenwich mean time], my attention was 
called to a splendid auroral arch ; the brightest I ever saw. Sky clear and calm blue, diffuse light 
in N. At lO"^ 11™. Centre of band over northermost of two bright stars in Gemini (Castor and Pol- 
lux). Motion at first a little northwards, but returned to its former position. Undulations of bright- 
ness from E. to W. passed along the zone. Began to break up from the E. end about lO'' IS": 
figure became irregular, and, on the whole, to the S. of its first position. 10*^ 22". Only streaks in 
the west remaining." 
March 18 10 2,5". The arch passed between the stars, 38 and 40 of the Lynx, which were nearly on the meridian ; 
at 10'' 32", the arch passed over the two stars, "K and ^tt Ursas Majoris. 
Diurnal Variation of Visible Frequency of the Aurora B or ealis . — When we note from the preceding Table 
the hours at which aurorse were seen at Makerstoun, we obtain the numbers in the following Table. 
Table 70. — Number of times that the Aurora Borealis was seen at Different Hours in the Years 
1843-9, as deduced from Table 69. 
Mak. 
Mean 
Time. 
Jan. 
Feb. 
March. 
April. 
Jlay. 
Aug. 
Sept. 
Oct. 
Nov. 
Dec. 
Nov. 
Dec. 
Jan. 
Feb. 
March. 
April. 
Aug. 
Sept. 
Oct. 
Year. 
5 P.M. 
1 
0 
0 
0 
0 
0 
0 
0 
1 
3 
5 
0 
0 
5 
6 ... 
4 
2 
0 
0 
0 
0 
I 
2 
7 
3 
14 
2 
3 
19 
7 ... 
10 
7 
4 
1 
0 
0 
2 
8 
. 7 
6 
23 
12 
10 
45 
8 ... 
9 
12 
9 
3 
0 
0 
5 
6 
9 
4 
22 
24 
11 
57 
!) ... 
10 
17 
12 
6 
0 
1 
10 
12 
16 
7 
33 
35 
23 
91 
10 ... 
8 
10 
13 
12 
3 
2 
7 
8 
9 
3 
20 
35 
17 
75 
1 1 ... 
4 
9 
10 
7 
2 
3 
5 
3 
4 
3 
11 
26 
11 
50 
12 ... 
4 
6 
8 
7 
2 
1 
2 
I 
3 
3 
10 
21 
4 
37 
1 A.M. 
2 
3 
5 
5 
1 
3 
2 
2 
2 
2 
6 
13 
7 
27 
2 ... 
3 
2 
3 
2 
0 
0 
2 
2 
0 
1 
4 
4 
15 
3 ... 
1 
0 
2 
2 
0 
0 
2 
3 
0 
1 
2 
4 
5 
11 
4 ... 
0 
0 
0 
0 
0 
0 
0 
2 
0 
1 
1 
0 
2 
3 
5 ... 
0 
0 
0 
0 
0 
0 
1 
0 
1 
1 
0 
1 
2 
