? 
lxxx GENERAL RESULTS OF THE MAKERSTOUN OBSERVATIONS. 
Gott. M. T. 
1849. a. h. 
Feb. 19 8 40™, Homogeneous auroral bank to N. with slight appearance of an arch. 
9 54™_58™, 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 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-dip ; 
the beams were but faintly 
visible, but they were obsery- 
ed to rotate about the point c, 
the centre of the corona, the 
beam a, appearing to occupy 
successive positions, till it F 
arrived at the position b; 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 nota 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.w. [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 10" 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 H. to W. passed along the zone. Began to break up from the E. end about 10% 18"; 
figure became irregular, and, on the whole, to the 8. of its first position. 10" 22™. Only streaks in 
the west remaining.” 
March 18 10 25™. The arch passed between the stars, 38 and 40 of the Lynx, which were nearly on the meridian ; 
at 104 32™, the arch passed over the two stars, A and #% Urs Majoris. 
Diurnal Variation of Visible Frequency of the Aurora Borealis —When we note from the preceding Table 
the hours at which aurore 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. | | | Nov. Feb. | Aug. || 
Mean Jan. Feb. | March.| April. | May. | Aug. | Sept. | Oct. Nov. | Dec Dec. | March.| Sept. |) Year. 
Time. } | Jan, | April. | Oct. 
“ilar eae | F | 
5 pM, l 0 0 0 0 0 OMe t Silees 5 ) ) 5 
Gxt: 4 2 Ol a|e 0 0 0 Le ee Tae 68 14 2 3 | 19 
Peal Or libs 4 ills ghlee| nt 0 2 meas 7 6 23 12 10 || 45 
8 9 12 9 BG) 0 5 omNG 9 4 22 24 11 | 57 
9 | 10 17 T2eline 1Goalene l On| eee 16590 7 33 35 23 91 
10 8 10 Sie || eda es 2 7) Nees 9 3 20 35 17 75 
1b 4 9 10 tae 3 5 3 4 3 11 26 11 50 
Pa 4 6 8 He le 1 2 1 Siac 10 21 4 37 
1 a.m. 2 3 5 5 1 3 2 2 ait 6 13 7 27. 
OW gael f 2 3 ea) 0 2 alee 0 1 4 7 4 15 
3 1 0 Pa EN CT 0 2 3 0 1 ee 4 5 11 
4 0 0 0 057} 20s le 10 0 2 0 1 1 0 2 3 
5 1 HO 0 0 0) S570 0 Calls Obie! 1 ) 1 2 
