558 



OBSERVATIONS ON THE ZODIACAL LIGHT. 



No. 279. 



JANUARY 12th, 1855: EVENING. 



Lat at 8k., 7 7' N. : Lon. 79 26' W. 



Sun set at 5A. 57Am. 

 Strouger Light at lit. 20m , &c. : Diffuse 7A. 30m. and 8A. 20;. 



Sky very fine for observations. Through want of care, I was a little later on deck than I ought to have 

 been. The following is my record for the evening : 



h. m. 

 'At 7 25, 

 7 29, 

 7 31, 

 32, 

 34, 

 36, 



ohr 



o7, 

 38, 



35, 



41, 



7 42, 

 7 43, 



44, 



45, 

 46, 



7 47, 



48, 



bright, and at b. 

 dim, and at a. 

 bright, and at b. 

 very bright, do. 

 dim, and at a. 

 still so. 



very bright, and at b. 

 still so. 



dim, decidedly, and at a. 

 brightening, 

 bright, 

 still so. 



(I notice, this evening, a decided difference 

 in the boundaries on the right or north- 

 ward, between the Light when bright 

 and when dim.) 

 still as at last. 

 , very bright., at b. 



do. do. 



dim, and at a. 



do. do. 

 bright, and at b. 

 , still so. 



50, very bright, do. 



h. m. 

 At 7 51, strikingly so, and at b. 



do. 



52, 



7 53i, 

 7 54i, dimmed. f 

 7 56^, brightening. 



7 57A, bright, and at b. 



8 0, the boundaries called b have been gradually 



extending beyond that, and have now got 

 to c. The zigzag has also just now as- 

 cended from x to y. 

 3, as at last, quite bright. 



Still SO. 



(i there seem to be pulsations in brightness, 



\ but not in boundaries. 

 8 10, dimmed, and boundaries not as distinct as 



before. 



8 12, same as last. 



8 13i, has just brightened considerably. 

 8 16, still as at last. 



8 20, do. do. seems to be permanent at this. 



9 0, the Zodiacal Light still decidedly marked in 



the sky, but gives no reliable boundaries." 



It may be well to repeat here, that, in these annotations about fluctuations, "do." means continued still at the same place, 

 t Passed Midshipman B was with me at this change, and remarked upon it at once, even before I had noticed it 



