STABILITY OF THE SYSTEM. 165 



Now is it probable that the occurrence of these 

 conditions of stability in the disposition of the 

 solar system is the work of chance? Such a 

 supposition appears to be quite inadmissible. 

 Any one of the orbits might have had any ex- 

 centricity.* In that of Mercury, where it is 

 much the greatest, it is only one-fifth. How 

 came it to pass that the orbits were not more 

 elongated ? A little more or a little less velocity 

 in their original motions would have made them 

 so. They might have had any inclination to 



Mercury and Mars, which have much the largest excentricities 

 among the old planets, are those of which the masses are much 

 the smallest. The mass of Jupiter is more than 2000 times that 

 of either of these planets. If the orbit of Jupiter were as excentric 

 as that of Mercury is, all the security for the stability of the sys- 

 tem, which analysis has yet pointed out, would disappear. The 

 earth and the smaller planets might in that case change their 

 approximately circular orbits into very long ellipses, and thus 

 might fall into the sun, or fly off into remote space. 



It is further remarkable that in the newly discovered planets, 

 of which the orbits are still more excentric than that of Mercury, 

 the masses are still smaller, so that the same provision is estab- 

 lished in this case also. It does not appear that any mathematician 

 has even attempted to point out a necessary connexion between the 

 mass of a planet and excentricity of its orbit on any hypothesis. 

 May we not then consider this combination of small masses with 

 large excentricities, so important to the purposes of the world, as 

 a mark of provident care in the Creator ? 



* The excentricity of a planet's orbit is measured by taking 

 the proportion of the difference of the greatest and least distances 

 from the sun, to the sum of the same distances. Mercury's great- 

 est and least distances are as 2 and 3 ; his excentricity therefore 

 is one-fifth. 



