50G OBSERVATIONS ON THE ZODIACAL LIGHT. 



No. 253. 



DECEMBER 12th, 1854: EVEN-INS. 



Lat. 38 2' N. : Lon. 122 7' W. 

 Sun net at 4A. 37 m. 



Stronger and Dilfuse Light at 



( 6/i. 15m. 

 ? 7 15 



( 8 10 



Sky clear, and very fine for observations. At 6 h 15 m , boundaries very well marked. I was particularly careful 

 this evening with reference to the sliding over of the Stronger Light as the night advanced. The sky was very 

 favorable for nice observations. The result is in the chart. The query is: Is the spreading out of the southern or 

 left boundary owing to the Zodiacal Light now crossing the ecliptic? or is it owing to the position at which we view 

 the Light ? The fact that, as the night advances, the southern boundary slides so as to approach nearer to a parallel- 

 ism with the ecliptic, seems to give an affirmative answer to the latter of the above queries. 



At 8" 1CP, the Light had dimmed, but was still bright ; and at 8" 21', it still gave well marked boundaries, the 

 same as at 8 h 10 m . 



