804 SPECIAL RESULTS IN THE URANOLOGICAL 



IRENE*: Hind, London, May 19, 1851; and De Gas- 

 paris, at Naples, May 23, 1851. 



In the above chronological review, ( 508 ) the primary 

 planets are distinguished from the secondary planets or 

 satellites by a difference of type. An asterisk has been ap- 

 pended to each member of that class of primary planets 

 which form a peculiar and very extended group, as it were 

 a ring of 132 millions of geographical miles in breadth, 

 situated between Mars and Jupiter, and are commonly 

 called the smaller planets, and sometimes telescopic planets, 

 co-planets, asteroids or planetoids. Of these, 4 were disco- 

 vered in the first seven years of the present century, and 

 10 in the course of the six years which have just terminated 

 a result due less to the improvement which has taken 

 place in telescopes, than to the diligence and skill of ob- 

 servers, and in particular to the improved star maps, which 

 have been so greatly enriched by the addition of stars of the 

 9th and 10th magnitudes. Moving points are now more 

 easily distinguished from among the adjacent unmoving or 

 fixed stars (See Pirst Part of the present volume, p. 98-99 ; 

 and in the original German, S. 155). The number of the 

 primary planets has been exactly doubled since the publica- 

 tion of the first volume of Kosmos ( 509 ), so quickly have 

 discoveries succeeded each other, so rapid has been the ad- 

 vance in the extension and completion of the topography of 

 our planetary system. 



2. Distribution of planets into two groups. If, in the 

 solar domain, we regard the region of the small planets situ- 

 ated between the orbits of Mars and Jupiter, but nearer on 

 the whole to the former than to the latter, as a dividing 



