542 OBSERVATIONS ON THE ZODIACAL LIGHT. 



No. 271. 



DECEMBER 30th, 1854: MORSIBG. 



Lat. at 4A., 10 46' N. : Lon. 89 31' \V. 



Sun rose at (ih. ~Zlm. 

 Stronger Light at 4A. lorn : Diffuse at 4/i. 20m. 



The sky was cloudy at 3" ; but by 4 o'clock it bad clsarel off again, and was very favorable for observations. I 

 was again particularly exact in getting boundaries, on account of the great c!r.i:ige which his occurred in the angle 

 between the axis of the Zodiacal Light and the ecliptic. It will be observed from the chart, that the latter, in this 

 latitude, and at this time, is nearly at right angles with the horizon. I also, this morning, gave attention to the 

 stars as seen through the Zodiacal Light, and found, even to 4" o(T, when the effulgent Light below the zigzag lines 

 is very strong, that with the naked eye I could readily make out stars of the 6tli magnitude within the effulgent 

 Light; for instance, the group of stars just south of 38 Librre (shown by dots at a on the chart), and also a single 

 star of 6th magnitude between 33 and 48, and 49 of do. (see dots at b on the chart) ; also a line of four stars below ID 

 Libr;B, and ranging with /? Libne (see dots at c on the chart) ; the two northernmost of these last are of the 

 7th magnitude, yet I think the naked eye detected them, even within this effulgent Light ; but the last are 

 near its upper edge. All this shows the great transparency of the substance giving the Zodiacal Light. At 4 1 ' 41'", 

 this effulgent part, which hitherto had been a warm light of great brightness, almost suddenly became a cold 

 whitish light, at the same time sinking down and spreading at its base on either side. At 4'' 46 m dawn 

 fully showed itself. 



