102 Mr. Henry Wilde on a 



examine the law more closely with a view to ascertain the 

 causes of the anomalous departures from it. 



On comparing the theoretic with the actual planetary 

 distances, it will be seen that most of the differences have 

 the same minus sign, or, in other words, are less than the 

 theoretic distances. So close, in fact, is this relation that, 

 the rsVo P art °f tne radius vector of Jupiter; an indefinitely 

 small amount of the earth's mean distance ; and ^ part of 

 the radius vector of Venus, would make all the actual 

 planetary distances less than the theoretic distances. The 

 addition of the small fraction 0*024 to Bode's constant 0*4, 

 also makes the minus differences absolute, without materially 

 affecting the theoretic distances, as shown in the last 

 column of the table. 



So far as I know, these numerical differences have never 

 before been recognised by astronomers, and add immensely 

 to the evidence in favour of the absoluteness of the primor- 

 dial law of multiple proportions of the planetary distances. 



On comparing the actual radii vectores of the planetary 

 orbits with Bode's numbers, it will be seen that the greatest 

 minus differences are in the outer planets. Thus the 

 difference of Saturn is 04.6 ; Uranus 04.1 ; and, notably 

 Neptune, which has the anomalous minus difference of 874. 



The relative order, motions, and magnitude of these 

 bodies point to their mutually disturbing attractions as the 

 primary cause of the departure from the exact multiple 

 proportions of their mean distances, although the influence 

 of a resisting medium is not necessarily excluded. 



Suggestions have been made that there may still be 

 another planet outside the orbit of Neptune ; but as there 

 is no evidence to indicate the existence of such a body, we 

 may conclude that Neptune is the outermost member of 

 the solar system, and, consequently, is subject to the dis- 

 turbing influences of all the major planets to contract his 

 radius vector to a much greater extent than any of the 



