510 OBSERVATIONS ON THE ZODIACAL LIGHT. 



X... 255. 



DECEMBER 15th, J854: EVI-.NINO. 



Lat. 37 48' N. : Lon. 132 21' \V. 



Sim set at 4/i. 39m. 

 Stronger and Diffuse Light at 9/i. 20m. 



Last evening too hazy for reliable results. So, also, at the early part of this evening. 



I have for three or four nights past noticed what seemed to be a great ascent of the Zodiacal Light in the sky 

 towards 9 o'clock ; but the Light was so dim, and the appearance was so strange and unusual, that I was unwilling 

 to make any record of it, until further and more decisive observations ; so anxious am I to guard against optical 

 illusions. But this evening, the sky at 9 h being particularly clear and favorable, this extended Light was so decided 

 that I could no longer hesitate. To make the matter more certain, however, I took the quartermaster on watch, and, 

 pointing out an extent of one quarter of the sky southward of the Milky Way, asked him to say whether he thought 

 any one part was brighter than the rest. He replied, " Oh yes, and I can tell you at once where it is ; for I have been 

 observing it several nights." He then gave the outlines as I have drawn them in the chart for the Diffuse Light, 

 except that he did not carry them higher than 71 Piscium, near where I have made the Stronger Light terminate. I 

 had no difficulty in making out the boundaries of both Diffuse and Stronger Light. 



At 10 h 3(P there was only a slight discoloration of the sky in that portion of it lying within the limits given at I)' 1 

 20"', and no reliable boundaries could be drawn. 



