196 OBSERVATIONS ON THE ZODIACAL LIGHT. 



No. 98. 



JANUARY 3d, 1854 : EVENING. 



Lat. 22^ 18' K.: Lon. 114^ 10' E. 



Sun set 5A. 25m. 



Eastern Zodiacal Light at 11A. ZOm. and midnight. Western, Stronger Light at !)/;. 40m Diffuse 9A. 20?n. 



10 10 



Midnight 

 i o'clock. 

 



Moon interfered till some time after nine. At 9 h 40" got observations. Night a most favorable one, calm and very 

 clear; sky brilliant. For observations, see chart. At 12 h (midnight), the Light was still very decided in the west 

 quite distinct. At I' 1 a. m. there was the slightest possible tinge; same boundaries as at 12 h . At l h 23 m the western 

 Zodiacal Light was still visible, but very faint; no boundaries could be got. At l h 32 m it was gone. There was then 

 a slight haze along the western horizon, but not high; and there was no light between it and the Pleiades. The 

 .Zodiacal Light had evidently died out. 



At II" 1 1 turned to the eastern horizon to observe there also. My notes are as follows: ''At ll h , there seems to be 

 a faint tinge in the eastern sky, as high as Prsesepe, and with the usual Zodiacal Light boundaries ; but cannot 

 speak positively not certain. At ll h 20 m , I think I can speak positively; got boiindaries; ll h 30", it seems to be 

 quite certain; the Light about Mars i. e. above TY and 78 Leonis Majoris is equal to that of the Milky Way close to 

 Procyon, but has the warm tinge of the Zodiacal Light; the western Light is of the same strength; ll h 40 m , the 

 eastern Light is certain now; it is stronger than that in the west." All this gradual growing, with the certainty 

 at ll h 40, makes it, I think, sure that I saw it at 11 o'clock. As the western Light continued till l b 23 a. m., both 

 eastern and western Lights were, consequently, simultaneously visible for two hours and twenty-three minutes. 



