THE ASTEROIDS BETWEEN MARS AND JUPITER. 367 



From 2.45 to 2.55 3 asteroids. 



From 2.55 to 2.05 26 asteroids. 



From 2.G5 to 2.75 28 asteroids. 



From . . 2.75 to 2.85 . v 10 asteroids. 



From 2.85 to 2.05 (i asteroids. 



From . . 2.95 to 3.05 10 asteroids. 



From 3.05 to S.lo 19 asteroids. 



From 3.15 to 3.25 9 asteroids. 



From 3.25 to 3.35 1 asteroid. 



From 3.35 to 3.45 3 asteroids. 



From ». . ..3.45 to 3.55 2 asteroids. 



Exterior to 0.00 L> asteroids. 



In three portions of the ring the clustering tendency is here distinctly 

 evident. These are from 2.35 to 2.45, from 2.55 to 2. SO, and from 3.05 

 to 3.20. V\'e have thus an obvious resemblance to the rings of Saturn; 

 the partial breaks or chasms in the asteroid zone corresponding to the 

 well-known intervals in the system of secondary rings. It may be re- 

 marked, moreover, that all but one of the nineteen asteroids between 

 2.75 and 2.85 are found in the inner half of the division ; the outer half 

 containing the distance at which five periods of a minor planet would 

 be equal to two of Jupiter. 



THE ECCENTRICITIES. 



9. The mean eccentricity of the asteroids is 0.15G83, while that of 

 the eight major planets is 0.0G025. It is worthy of note, however, that 

 Mercury's eccentricity (0.20549) is even greater than that of the minor 

 planets, and that the mean eccentricity of Venus, the Earth, Mars, 

 Jupiter, Saturn, Uranus, and Neptune is but 0.03949. Of the asteroid 

 orbits the least eccentric is that of Lomia, 0.02288 ; the most eccentric, 

 that of JEthra, 0.38200. As with the orbits of the old planets, the 

 eccentricities vary within moderate limits ; some increasing, others 

 diminishing. The average, however, will probably remain very nearly 

 the same. The facts above noted indicate that the form of tlie orbits 

 of Mercury and the asteroids was influenced by special causes. The 

 mean eccentricities in the several parts of the asteroid zone are as fol- 

 lows : 



Interior to 2.25 0. 1G307 



From . . . .2.25 to 2.35 0. 15644 



From.... 2.35 to 2.45 0.14930 



From .... 2.45 to 2.55 0. 13094 



From.... 2.55 to 2.G5 0. 1G2SG 



From....2.G5 to 2.75 0. 17210 



From.... 2. 75 to 2.85... 0.15474 



From .... 2.S5 to 2.95 . : 0. 18839 



From.... 2.95 to 3.05 0. 2G182 



From.... 3.05 to 3.15 0.13541 



