6'j8 HIKKKLA.ND. TI1K NORWEGIAN AURORA 1'OLAKIS F.XI'EI HI 'ION, 1 9<32 1903. 



It slunild be stated, however, that on several occasions when JONKS believes he has seen pulsations 

 no corresponding magnetic pulsations were traceable at Greenwich. Whether the reason of this is that 

 the original photographic curves have been much obliterated, can scarcely be determined. 



On the Plates, where Gottingcn mean solar time is employed, the time is marked when JONES has 

 observed pulsations in the xodiacal light (Z. L. P.). 



It will be seen that this period that for the 271)1 March falls at the end of a series of exceedingly 

 distinct magnetic pulsations, which are in quick-run magnetograms usually called Escherihagen 

 oscillations. These are especially distinct in //, but thev would also certainly have been distinct in D 

 in the original curve. 1 lere, however, they have been fainter, and the curve has been drawn principally 

 as a mean line, whereby these oscillations have been eliminated. 



On the 30th January too, the pulsations occur at the end of a series of particularly characteristic 

 magnetic pulsations. The latter are especially distinct in the period immediately preceding Jones' observa- 

 tions, but also undoubtedly seem to continue, although less powerful, during that period. The curves 

 here, however, have been somewhat obliterated and are difficult to follow in detail. 



In the magnetic curves on the other two Plates, there are rapid oscillations of comparatively long 

 duration. These, however, are not such typical elementary waves as the preceding ones. 



We finally append JONES' notes from the first two days mentioned, a, />, and d here indicate the 

 special boundaries of the zodiacal light, which are given in the figures in his work. 



JANL'ARV 3oth 1854: KVK.MM,. Lat. 26 jo' N. Lon. 127 42' 1C. 



Sun set 5 1 ' 38' o m . 



Stronger Light 7'' 50"'. <Vc: Diil'nse, (7)11 =;o m . 

 Sim's Lon. 310 20'. 



There can lie no doubt thai there arc pulsations in the Zoihacal Light. I noticed them last evening 

 (the sky being very clear); but, it being Sunday, made no particular record of them. They were, 

 however, distinctly to be seen; and when 1 called the attention of one of the quartermasters to them, he 

 very easily made them out. His language about the Light was: "Now it seems to be dying away"; 

 "now it is brightening again", .Vc. All this applied, however, only to the Stronger Light: it occurred 

 between 7'' 30 and 8 o'clock. This evening 1 was on the careful lookout for them, and, with watch 

 in hand, made record of the changes and their times. Clouds interfered till 7'' 50'", when, this part of 

 the sky having cleared up, I got observations. The pulsations were very distinct; observable, however, 

 only in the Stronger Light. This, at / h 50, had its boundaries as in the line /; (see chart), and was 

 very bright: 7'' 52'" it had sunk to the boundaries marked a and was very dim: 7" 54'" had risen to b 



again, and was bright: 7'' 55'" at a, and very dim: / h 56 at b, and brigth: 7'' 57'" at a and very 

 dim: 7'' 58' '.>'" at h, and bright: 7'' 59' V 11 still at b, and bright: it seemed now to be permanent at b; 

 but clouds soon after spread over the sky, ami shut out everything from sight. 



These pulsations, in order to be seen, seem to require that the ecliptic should be at a high angle 

 with the horixon ; at which time the Stronger Light is very brilliant. 



MARCH 27th 1854: LVKNING. Lat. 35 26' N.: Lon. 139 42' 1C. 



Sun set 6'' 12' ;> m - 



( -jh 30 m ^ 



Stronger Light | gh 3Qm j Dilluse at 7!' 30, &c. 



Sky remarkably clear. The following are my notes: 7'' 15'" a whiteness running up with the 

 Zodiacal Light boundaries as far as the Pleiades, but its limits are not distinct: 7'' 24'", the light more 

 decided, but its boundaries not reliable : 7 b 30'", got boundaries of both Diffuse and Stronger Light the 

 latter, then, strong up to /;, and gradually tapering, dimming off to c. 



