OBSERVATIONS ON THE ZODIACAL LIGHT. 



No. 56. 



SEPTEMBER 15th, 1853 : MORNING. 



Lit. 23 3 2' N. : Lon. 113^ 28' E. 



Sun rose 5A. 50m. 



Stronger Light 3/i. 15in. Diffuse Light 3A. 15m. 

 40 40 



4 20 

 4 26 



Moon set at 3" 15 m . Had a good observation immediately afterwards, and also at 4". At 4 h 20 m , the Diffuse Light 

 was too faintly marked to give a reliable outline. The Stronger Light now becomes more and more intense till just 

 before dawn; then it begins to spread laterally; finally, it gradually melts into the dawn. I noticed this morning, 

 that this lateral spreading is more rapid and greater towards the N. than towards the S. ; its boundaries at 4" 26 m arc 

 marked by the dotted line: at 4 h 30 m it was merged into dawn. 



