of November 1836. 91 



I have been somewhat disappointed that the astronomers 

 should have paid so little attention to the remarkable changes 

 which take place in the zodiacal light about the 13th of Novem- 

 ber, as has been repeatedly mentioned in this Journal. It ap- 

 pears to meafact deserving theirattention, that the zodiacal light, 

 which for weeks before the 13th of November appears in the 

 morning sky, with a western elongation of from 60 to 90 degrees 

 fi-om the sun (while up to that time not a glimpse of it can be 

 caught in the evening sky), should immediately afterwards ap- 

 pear after the evening twilight in the west, and rapidly rise 

 through the constellations, Capricornus and Aquarius, to an 

 elonsation of more than 90 degrees eastward of the sun, while 

 it as rapidly withdraws itself from the morning sky, and with- 

 in a few days vanishes entirely from the western side of the sun. 

 For three years past I have observed these changes with much in- 

 terest, and feel warranted in asserting that they have been re- 

 peated with uniform regularity. The present year the light was 

 very feeble in the morning sky, an effect partly owing to the pre- 

 sence and pecuHar splendour of the planet Venus ; but as soon 

 after the 13th of November as the absence of the moon Avould 

 permit observations^ the light appeared in the west immediately 

 after twilight, crossing the Milky Way, and rising in a pyramid 

 almost as bright as that, the triangular space between it and the 

 Galaxy, embracing the Dolphin, appearing by contrast strikingly 

 darker. 



I can account for this great and rapid change of place in the 

 zodiacal light, a change which is unlike any it sustains at any other 

 period of the year, only by supposing that on or about the 13th 

 of November it comes very near to us, and that we pass rapidly 

 by it, thus giving it a great parallactic motion, an effect which 

 is in perfect accordance with all our previous conclusions. 



According to this view of the subject, the zodiacal light zcould 

 no longer be regarded as a portion of the sun^s atmosphere^ but 

 as a nebidous or cometary body, revolving round the sun icithin 

 the eartKs orbit, nearly in the plane of the solar equator, ap- 

 proaching at times very near to the earth, and having a perio- 

 dic time of either one year, or half a year, nearly. 



Such, I affirm, would be the fact should the zodiacal hght be 

 proved to be the body which affords the meteoric showers, 

 yale College, Dec. 19- 1836. 



