14 OBSERVATIONS ON THE ZODIACAL LIGHT. 



No. 7. 



APRIL 9th, 1S53 : EVENING. 



Lat. 223 is'N.: Lon. 114'- 10' R. 

 Sun set fi/(. 14m. 



Stronger Light j ^ ^'"' j- Diffuse. T/i. i:.m. 



Clouds in the morning. This evening, just along the horizon, ha/,y: but otherwise a good night for observation. 

 In the early part of the evening, the outlines of the Stronger Light \verc at : the I.) i if use is marked also on 

 the chart. Wishing to make this evening's observation a particularly caivl'nl cue, on account o!' this singular sliding 

 over of the light, I called two of the quartermasters,* separately, and asked them to tell me where the Stronger 

 Light was. without putting any leading questions to them, or telling them my object. The first replied: "It is 

 considerably brighter to the right of that star (Saturn) than it is to the left: that star is its left-hand limit. : 

 Oh! yes, sir, the principal partis on the right of it." (Saturn). The other, to my question where the brightest 

 part, was, replied: "Well, 1 fancy it's to the right of that star (Saturn). Yes; that's the brightest place, right 

 under that group of stars, ( Pleiades,) and to the right of that star" (Saturn). This was at ?" '20 ra . At 7 U 45" I 

 called them again, and also Dr. - , and asked them separately. Dr. - - described the outlines in the sky, 

 and I drew them on the chart at b I It by his description. The two quartermasters gave the same boundary. It 

 corresponded also to my own views ol' the case. 



HJi nil- nil ilicfii' on/liitrs n/rii/ In' full ij rt'liril on. I notice, also, that, as the evening advances, the Diffuse Light on 

 the right, of Arietis, and so up, entirely disappears. I have thought so for several evenings; this evening it was 

 decidedly so. 



[Brooklyn, May 'Jfi, IS.',!',. These lateral changes of the whole body ol' the Sinmger Zodiacal Light are very 

 remarkable. I cannot see any room Ibr mistake; as there might have been, had the Light been more inclined to the 

 horizon. But the horizon and ecliptic made nearly a right angle. My own change of place, as respects the ecliptic, 

 during the interval of observations, does not meet the case. The gn-al inclination or' the Light, to the ecliptic is also 

 noteworthy. This latter circumstance appears also in the observations of March 30th and 31st, 1S.">:J; on which 

 occasions, however, I noted only the Dilfusc Light.] 



> It may be well to say to lundsmrn. (hut quartermasters are among the highest petty officers in mir ships. They arc taken fivim the oldest and 

 most reliable among the seamen. In [mrt, nne, and at sea, two, uf them must always lie mi deck, day and night, on watch or other duty. 



