1 It 



KNOWLEDGE. 



May, 1015. 



intellectual eminence, but of the real giants, we 

 believe that the great discoverers represent indi- 

 vidual mutations. In its finest expression the dis- 

 covering spirit means a particular alertness, fresh- 

 ness, eagerness, insight, and cerebral potential — 

 born, not made. The spot of light which marks its 

 emergence shifts from place to place, from nation- 

 ality to nationalitv. from race to race, from 



university to university, shining forth now in Pisa 

 and again in Paris, now in London and again at 

 Leyden, now in Brussels and again at Berlin, 

 now in Edinburgh and again in Petrograd, now 

 in Amsterdam and again in New York. It is a 

 rare spirit, sacred and inestimable, and moveth 

 where it listeth, no one being able to tell whence 

 it cometh, or whither it goeth. 



SOLAR DISTURBANCES DURING MARCH, 1Q15 



Bv FRANK C. DENNETT. 



With the exception of the 3rd, the Sun was under observ- 

 ation every day in March, and was never free from spots ; 

 whilst on the 2nd as many as seven distinct spot disturbances 

 were visible at one time. The longitude of the central 

 meridian at noon on March 1st was 34° 8'. 



Nos. 18, 20, 21, 23, 24, and 25 of the February list con- 

 tinued on the disc until March 2nd, 5th, 6th, 10th, 2nd, 

 and 10th respectively, and therefore reappear upon the 

 present chart. 



N<> 26 appeared as pores a little south-west of No. 23 

 on the 2nd. The leader increased to seven thousand miles 

 in diameter, but the others died out. Last seen on the 9th. 



No. 27. — A double group of spotlets and pores, constantly 

 changing their appearance ; seen from the 6th until the 

 11th. Its greatest length was sixty-four thousand miles. 



No. 28. — A line of four or five pores, fifty-seven thousand 

 miles in length, in a faculic bed ; seen from the 7th until 

 the 13th. 



No. 29.— A fine spot, twenty-one thousand miles in 

 diameter ; close to the north-eastern limb on the 7th. On 

 the 9th it appeared triangular ; next day its umbra was 

 bridged, and two pores followed it. The pores constantly 

 changed position, and on the 14th a bridge of the photo- 

 spheric matter entirely crossed the spot from north to 

 south. Last seen amid faculae, close to the north-western 

 limb on the 19th. 



No. 30. — Broke out on the 14th, close to the central 

 meridian, the northern spotlet being the largest. Next 

 day a line of spots and pores. The length was thirty-two 

 thousand miles, and one of the rear spots became ten 

 thousand miles in diameter. Last seen close to the limb 

 on the 20th. 



No. 31. — A group of spots and pores very protean in 

 character, thirty-five thousand miles in length ; seen from 

 the 17th until the 22nd. It attained its maximum size 

 on the 20th. 



No. 32. — A solitary pore only seen on the 20th. 



No. 33. — A curved line of pores in a faculic bed, some 

 thirty-five thousand miles in length; seen from the 21st 

 to the 23rd. 



No. 34. — A spot some twelve thousand miles in diameter, 

 first seen on the 23rd. Pores were following it on the 27th, 

 29th, 30th, and 31st. Last seen on April 2nd. The length 

 was thirty-four thousand miles. 



No. 35.- — A faculic area had been coming round the south- 

 eastern limb since March 19th, and on the 29th two pores 

 were seen ; the leader increased to a spotlet by the 30th, 

 and other spores had developed. The pores not seen after 

 April 1st, or the spot after the 4th. Its greatest length was 

 twenty-nine thousand miles. 



No. 36. — Two pores, each situated in a facula, fifty-two 

 thousand miles apart ; only seen on the 29th and 30th. 



No. 37. — Altogether the finest group seen for several 

 years. First seen as a line within the north-eastern limb 

 on March 29th. Next day it was evident that a considerable 

 group was formed. At first there was a great leader, over 

 forty thousand miles in diameter, followed by a group of 

 spots, which by April 4th had developed into a fine oval 

 spot, thirty thousand by eighteen thousand miles in 

 diameter, containing two umbrae. Behind this were some 

 pores, and a smaller spot bringing up the rear. On April 

 7th a small spot and pores preceded the great spot, making 

 the total length of the group one hundred and eighty thou- 

 sand miles. It was closing up to the limb on April 10th, 

 the date of the last record to hand. It extended back into 

 the area of No. 27, and covered that of No. 16. 



No. 38. — A group thirty-one thousand miles in length, 

 consisting of five pores, broke out on March 30th, two of 

 which remained visible until the next morning, but were not 

 seen subsequently. 



Faculae were recorded within the north-western limb 

 on March 7th to 10th, 14th, 25th to 27th, and 29th to 31st ; 

 north-east, 1st, 2nd, 9th, 10th, 16th, 19th to 22nd, 27th, 

 28th, and 31st; south-west, 6th, 7th, 9th, 11th to 14th, 

 27th, 30th, and 31st; and south-east, 2nd, 19th to 22nd, 

 and 26th to 31st. 



Our chart is constructed from the combined observa- 

 tions of Messrs. John McHarg, \Y. J. Waters, and F. C. 

 Dennett. 



DAY OF MARCH, 1915. 



