208 Prof. Norton on Molecular Physics. 



becomes 348°. The average position of Saturn at the epochs of 

 maxima was 236°. 



If we now direct our attention, to the first two epochs of 

 maxima, we shall perceive that Jupiter was in that part of the 

 ecliptic in which his ordinary action is the least ; and if we refer 

 to the first two epochs of minima, it will be seen that he was in 

 or near the part of the ecliptic in which his ordinary action is 

 the greatest. We must conclude, then, that from 1750 to 1766 

 the normal condition of things at the two nodes was greatly 

 changed, and that the action of Saturn conspired with that of 

 Jupiter to produce the anomalous results. 



In view of the general results that have now been obtained, 

 we may infer (1) that in general the action of a planet to pro- 

 duce spots is greatest in the portion of the ecliptic which con- 

 tains the descending node of the secondary magnetic equator, and 

 least in the opposite portion; (2) that the action is approxi- 

 mately the same at corresponding points on one side and on the 

 other of either node. Bat the indications are that a somewhat 

 greater liability to epochs of maxima exists when the planet is 

 on the side of the line of the magnetic nodes toward which the 

 progressive motion of the sun is directed than on the opposite 

 side. This is most observable in the case of Saturn ; for his 

 average position at the epochs of maxima was 236°, while that 

 of Jupiter was 183°. 



By an examination in detail of the diverse positions of the 

 operating planets at all the different epochs, and following their 

 motions from one epoch to another, it may further be shown 

 (1) that a planet operates more effectively before and after it has 

 passed either magnetic node than at the very node ; (2) that the 

 normal positions of the two nodes are not far from 0° and 180° 

 of longitude, the sun's rotation having the effect to displace them 

 about 1 7° toward the east (p. 206); (3) that the principal maxima 

 of planetary action occur at about the positions 135° and 230° 

 on opposite sides of the descending node, and that under cer- 

 tain circumstances other positions of inferior maxima manifest 

 themselves, lying in the vicinity and on opposite sides of the 

 ascending node ; (4) that the principal minimum falls at about 

 0°, or at the ascending node, and a secondary minimum at 180° 

 (or the descending node) ; but in the normal state of things the 

 effect of the planet appears to experience small changes in the 

 space from 320° to 70°. These positions of maxima and minima 

 are given here only as first approximations. 



These results of observation, deducible for the most part from 

 the Table we have given (p. 207), and confirmed by a detailed 

 examination of Professor WolPs entire series of determinations, 

 are all decided intimations of a dependence of the sun's spots 



