[ 246 ] 

 XXIX. Intelligence and Miscellaneous Articles, 



ON THE PERIODICITY OP THE SOLAR SPOTS, AND INDUCED 

 METEOROLOGICAL DISTURBANCES. 



To the Editors of the Philosophical Magazine and Journal. 



Gentlemen, 



ASSUMING the mechanical energy exerted by the sun, as ex- 

 hibited in its heat, light, and magnetism, to be directly created 

 and sustained by the simplest yet grandest of the solar forces and 

 motions, viz. by the force exerted by the planetary bodies (through 

 gravity) acting upon the matter of the sun in rapid revolution around 

 its axis (producing, if that matter be in a solid or coherent state, a 

 violent and variable degree of tension, and if fluid, a violent agitation 

 in eddies or tides), — would it not be reasonable to suppose that the 

 orbital positions of the planets, especially at particular times, would 

 not be without an effect as a disturbing element in the physical 

 energy exerted by the sun itself ? 



It might even be natural to suppose that when the principal or 

 larger mass of the planets are in (or nearly in) conjunction on 

 one side of the sun in their orbits, such a disturbance would take 

 place, owing to the centre of gravity of the solar system moving or 

 shifting its position within the body of the sun itself, from an in- 

 creased pull, or amount of attraction, exerted in one particular 

 direction. May not some such disturbance be even at this moment 

 taking place, and from this very cause ? We have Venus, Jupiter, 

 Saturn, and Uranus, all on one side of the sun, nearly in conjunc- 

 tion ; and we have likewise seen during the whole of the present year, 

 more or less, a great solar disturbance taking place, as proved by the 

 unusual number of spots that have been visible. 



Schwabe has proved that there is a spot-period, of about 11*1 

 years from maximum to maximum ; and Col. Sabine, that this period 

 coincides again with a particular class of magnetic cycles. It would 

 indeed be a notable point gained to science, if the magnetic con- 

 dition or force of the sun itself could be shown to depend upon, or 

 possibly resolve itself into (as a correlated force), the force of gravi- 

 tation itself ! The most important thing then to ascertain is, whether 

 or not a certain position of the planets in their orbits does not tend 

 at certain times, through the force of gravitation, to create mag- 

 netical disturbance and increased mechanical energy in the sun? 

 Jupiter, as far the largest planetary mass, would naturally have a pre- 

 dominating effect, and would tend to regulate the period of pertur- 

 bation. Wolf, Carrington, and others have, I understand, already 

 considered as more than a coincidence, the Jovian period of nearly 

 12 years, as connected with the spot-period of 11*1 years, without, 

 however, arriving at any precise or definite results. 



It would be desirable to ascertain how far the variations in the 

 belts and markings on Jupiter himself agree with the spot-periods of 

 the sun ; it is more than possible that a mutual connexion might be 

 traced. 



Should the extremely cold, wet, and windy weather experienced 



