}2() OBSERVATIONS ON THE ZODIACAL LIGHT. 



No. CO. 



SEPTEMBER 30th, 1853: MORNMO. 



Lat. 22 23' N.: Lon. 113 32' E. 



Sun rose 5A. 55m. 

 Stronger Light at 3h. Om. Diffuse at 2/i. Om. 



2 30 



3 



The sky, this morning, was remarkably clear so clear, that I could easily see stars of the 6th magnitude with the 

 naked eye. Rose at 1" 30, and was on deck till the moon showed itself, near halt-past 3. Observed very carefully, 

 in order to see at what time the Zodiacal Light would first show itself. It was at two o'clock that I could first make 

 it out: it was dim. At 2" 15 m , it was decidedly exhibited; at 2" 30 m , the Stronger Light developed itself, and at 3", 

 it was strong enough to give me its outlines reliably. As the moon was now approaching the horizon, I watched to 

 see whether it would increase the brightness of the Zodiacal Light, and was pretty well satisfied that it did. The 

 Zodiacal Light changed gradually from its former soft color into a hard white, and grew brighter and brighter the 

 limits df the new brightness keeping between 11 and 16 Hydra 1 , and 48 Cancri till just before the moon rose, when 

 they suddenly expanded along the horizon. The unilluminated part of the moon (which was uppermost) was so 

 bright as to show itself most distinctly. Query: whence came the light illuminating that portion of the moon so 

 greatly ? 



[P. S., 1856. Was it from the Zodiacal Light ?] 



