PORTION OF THE COSMOS. THE PLANETS 305 



zone in space, or as forming, as it were, a middle group ; 

 then, as has been already remarked, the inner planets 

 those which are nearer to the Sun viz. Mercury, Yenus, 

 Earth, and Mars present many points of resemblance to 

 each other and of contrast to the outer planets Jupiter, 

 Saturn, Uranus, and Neptune situated further from the 

 Sun, beyond the dividing zone. The middle group of the 

 three, or that of the small planets, scarcely occupies half the 

 interval between the orbits of Mars and of Jupiter. In 

 the space between these two greater planets it is the part 

 nearest to Mars which, so far as our present knowledge 

 enables us to judge, is most richly furnished ; for if, in 

 the zone of the asteroids, we consider the extreme ones on 

 either side Flora and Hygeia we find that Jupiter is 

 more than three times farther from Hygeia than Mora is 

 from Mars. This middle group is strongly distinguished 

 from the others by the intersecting, highly inclined, and 

 excentric orbits, and by the very small dimensions of the 

 planets of which it consists. The inclination of the orbits 

 to the ecliptic rises in Juno to 13 3', in Hebe to 14 47', 

 inEgeria to 16 33', and in Pallas even to 34 37'; while 

 in this same middle group it falls as low as 5 19' in Astrea, 

 4 37' in Parthenope, and even as 3 47' in Hygeia. The 

 small planets whose orbits have less than 7 of inclination 

 are, in descending order, Flora, Metis, Iris, Astrsea, Parthe- 

 nope, and Hygeia ; but in none of these are the inclinations 

 as small as in Yenus, Saturn, Mars, Neptune, Jupiter, and 

 Uranus. In exceutricity of orbit some of the small planets 

 exceed and some fall short of Mercury (0.206), Juno, 

 Pallas, Iris, and Victoria having 0.255, 0.239, 0.232, and 

 0,218 ; while Ceres, Egeria, and Yesta, have respectively 



