PROCEEDINGS OF THE CANADIAN INSTITUTE. Ill 



In au old " Loudon Almauack " I find there was about central on October 

 13th, 1869, a huge spot, 672,000,000 of miles in area, I therefore had to plot the 

 magnetic curve. No. 2, and it seems to show that the disturbance repeats after 135 

 rotations, but the spot has no relation to this storm ; it may, however, be the 

 outcome of the solar disturbance which caused the depression of September 14th, 

 a rotation before. The next curve. No. 3, is plotted to show at August 25th, 

 1872, the beginning of a storm which culminates on October 17th — 176 rotations. 

 It also shows the association of a spot and a disturbance in the beginning of 

 August, both of which are on another disturbed meridian which shows magnetic 

 effects in all the subsequent tracings and has spots associated with it in Nos. 

 5, 7 and 13. The two curves Nos. 5 and 6 are given because of a paper in the 

 "monthly notices" of the Royal Astronomical Society "On the great sun-spots 

 of 1882, April, also November 12th-15th." The day of centrality in 

 April is not given, but on the 17th there was a magnetic storm so 

 violent that it could not be completely registered. It can be traced back to 

 September 12th and October 9th of the previous year. The November sun-spot is 

 in the middle of a long and pronounced disturbance of the needles, the beginning 

 of which is 311 rotations subsequent to the storm of September 1st, 1859. In the 

 "monthly notices" there is a paper " on a remarkable sun-spot of 1886, April 

 24th." This is an instructive occurrence because there was no remarkable 

 disturbance of the magnets along with it (see curve No. 8), but there was a 

 disturbance on January 8th and 9th, with an accompanying spot ; there was 

 another on March 31st, which apparently gave rise to the spot which appeared the 

 month after. In these curves, especially in No. 7, the commotion with which it 

 began may be seen to continue. Curve No. 9 shows the depression figured in 

 detail by the late Professor Carpmael in the frontispiece of the Transactions of the 

 Astronomical Society for 1892, which produced the celebrated rose-auror;e of 

 February 13th, and what the Royal Astronomical Society's notices say was an 

 exceedingly large composite spot, the largest up to that time ever recorded. I 

 observed this spot with care and submitted a series of drawings of it to our 

 Astronomical Society. The spot had appeared during the previous rotation, 

 January 8-12, and the magnetic disturbance, which can be traced back to 

 September 25th, 1891, continued as regularly as could be expected, considering the 

 immense solar area involved, well into 1893. You may see that it kept on causing 

 spots, shown in curves Nos. 10 and 11. The Toronto Astronomical Society 

 records in 1898, September 2nd-15th, a spot 65,000 miles long and 75,000 miles 

 broad, belonging to a disturbed area 150,000 miles across, and curve No. 12 

 shows the great magnetic depression which immediately followed it. Lastly I 

 give the location of the spot of May of the year 1901, which is rather celebrated, 

 though not a very large one. The Abbe Moreux, of Bourges, first saw it on May 

 20th, when it was so active that he thought the solar spot-minimum had suddenly 

 passed away. His vivid description of its rapid changes of form and division into 

 two main parts startled the world, who expected a scorching summer in 

 consequence, a fear which I attempted to allay by showing its small comparative 

 importance and the absence of great magnetic disturbances connected with it. Its 

 activity may, however, yet be important to science, as it was just on the edge of 

 the sun at the time of a total eclipse, and we may hear of moderate coronal 

 disturbances near the latitude it occupied. 



Physicists and astronomers are indeed now beginning to admit, with apparent 

 and unaccountable reluctance, the intimate connection between the two effects of 

 a common cause, sun-spots and magnetic storms. Mr. Wm. Ellis, F.R.S., says: 

 " the general effect observable is that in our latitude there may be at one time a 

 large solar spot with great magnetic disturbance ... at another time a 

 considerable solar spot may appear without accompaniment of unusual magnetic 

 movement ; and again, magnetic disturbances may occur without any noteworthy 

 spot." The " general effect " is not quite fairly stated, even by this most cautious 

 and painstaking official ; there seldom if ever is a great spot without a magnetic 

 storm with which it can be connected, usually while it is visible, occasionally a 

 rotation before. Mr. Ellis does not seem to have quite freed himself from the old 

 idea that spots cause storms, or fully to recognize either the cosmical nature of 

 magnetic phenomena or their effect all over the earth, else why does he allude to 



