INTRODUCTION. 



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coming into position for giving us visililc reflection : while portions l;)lely visible, were no longer 

 i;-ivitio- us such a reflection.* 



: The lirst. f'm- of these results were ni>t always uniform ; hut the exceptions were tew, ami wrrr probably occasioned by 



the nrliiikins ring's nut lyinu exactly in the ]ilai I' the elliptic. In order to afford (he reader a comprehcn>i\ e glance at 



tlii-, very important anil interesting part of our subject. I have drawn out a table. ;:mir_: tin- number of each chart, and its 

 bearing upon tin- above four general facts : jJ'i simiihing that the oKsei vation was in 1'avor of, and minus ap-ainst. that one 

 S the farts whose number immediately follows. An asterisk to any number signifies that the observation referred to is 

 of particular force. A note of iuten-.^ation means that the case is doubtful. The reader is especially requested to com- 

 pare the evening observations of October. IS.Vi, with those of December, in the same year. In both cases I was in the 

 same latitude ; hut in October, I was far north of the ecliptic, in the evening ; and in December, was nearly on that line ; 

 and the change in the Zodiacal Light boundaries is correspondingly great. Compare also the evening observations of 

 March 16th, 1855 (No. 303), with the morning observation of the same night (No. 304). In the former case I was far 

 removed from the ecliptic ; while, before morning, I was brought close to it, with a corresponding change in the place of 

 the Zodiacal Light. Compare also the whole series of observations from Nos. 49 to 82 ; where, in the morning, I was near 

 the ecliptic, and in the evening, far removed from it. Observe also how, as in the latter part of October, and in Novem 

 ber of that year (1853), I was each evening drawing rapidly more and more towards the ecliptic, the Zodiacal Light was 

 also rapidly withdrawing from the north, and was drawing up towards the ecliptic line. 



In constructing this table, I have had reference chiefly to the Stronger Light, as giving us the most reliable data. 



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