ZODIACAL STELLAR CHARTS. 



amateur as well as professional, for the spirit and perseverance 

 with which they have undertaken the preparation of these 

 Zodiacal Stellar Charts. Mr. Cooper of Sligo, and his assistant 

 Mr. Graham, are understood to be thus occupied. They have 

 already published three volumes containing the approximate posi- 

 tions of more than 45000 stars. Professor De Gasparis, of Naples, 

 and Mr. Chacornac, of Paris, are similarly engaged. 



In further illustration of the table annexed to this notice, Mr. 

 Bishop adds the following observations : 



The fourth column contains the estimated magnitude or degree of bright- 

 ness of each planet at the time of discovery. It would appear that the 

 four which attain the highest degree of brilliancy are Vesta (often visible 

 without a telescope), Pallas, Iris, and Flora. 



The fifth column gives the mean longitude for noon, Greenwich time, 

 on the 1st of January, 1855, reckoned from the equinox of that date. 



In the sixth is found the longitude of the perihelion, or nearest point of 

 approach of each planet to the sun, as viewed from that luminary. 



The seventh contains the position of the ascending node, or the point in 

 the ecliptic where the planet passes from south to north latitude, as viewed 

 from the sun. 



The eighth shows the inclination of each orbit to the ecliptic, or the 

 angle between the planes of the paths of the earth and planet. It will be 

 remarked that Pallas, Euphrosyne, and Phocea, have the largest inclina- 

 tions, while Massilia and Themis exhibit the least ; or, in other words, 

 revolve nearly in the ecliptic. 



The ninth column expresses the amount of excentricity or deviation 

 from the circle. It varies from 0*075 in the case of Amphitrite to 0'346 

 in that of Polyhymnia. 



The tenth gives the mean daily sidereal motion, or the space through 

 which each planet would move in one day, if it described a circle round 

 the sun with its average velocity. The numbers in this column multiplied 

 by the periods expressed in days will, therefore, be equal to the circum- 

 ference, or 360. 



The eleventh shows the mean distances from the sun, or the semi-axes 

 major of the orbits, expressed in units of the earth's average distance 

 from that body, and carried to two places of decimals. Flora has the 

 least, and, according to the table, Euphrosyne the greatest ; though the 

 recent date of this planet's discovery, and consequent comparatively short 

 extent of observation, leaves us in a little uncertainty whether its mean 

 distance will ultimately be found to exceed that of Hygeia or Thernis. 



The twelfth shows the length of the sidereal revolution in days. The 

 periods vary from 1193 days, that of Flora, to 2048 days, which is that 

 of Euphrosyne ; the difference amounting to 855 days, or 2^ years. 



I have annexed to the table the thirty-fourth and thirty-fifth 

 planets discovered by Mr. Chacornac and M. Luther since Mr. 

 Bishop's table was printed. The elements of the last of these 

 objects, however, have not yet been determined. 



13. In their exceptional minuteness of volume, their mean 

 distances from the sun, and the very variable obliquities and 

 eccentricities of their orbits, they all resemble the first four dis- 



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