982 Transactions of the Amehican Institute. 



If these premises be all true, then it will follow that what wo 

 call the magnetic pole shall revolve about the polar axles of the 

 earth in the same time in which the earth movingc forward in com- 

 pany with the solar system performs a complete revolution rehx- 

 tively to that system around which the sun himself revolves. Let 

 me not be misunderstood; this is not the sun's period; that of 

 course is very much greater. The earth is only a satellite of the 

 sun, and in the revolution of which we speak she has but repeated 

 exactly, but on a grander scale, the same phenomena which our 

 own satellite, the moon, performs monthly; accompanying the earth 

 in her orbit, at the return of every full she has performed a com- 

 plete revolution, relatively to the sun's center, around which the 

 earth herself revolves. So also the earth, moving onward in 

 company with the solar system, performs a complete revolution, 

 relatively to that center around which the sun revolves in his orbit. 

 We have seen that the magnetic poles (for the north and south 

 poles revolve together) perform a complete revolution round the 

 north and south polar axles* of the earth once in al)out six hundred 

 and forty years, and hence we infer that in the same period of time, 

 the earth, still keeping her place in the solar system, performs a 

 complete revolution relatively to another and higher system around 

 which the sun himself, with all his attendant train, revolves. This 

 revolution is accomplished by the simple fact that, because the sun 

 is in motion in an orbit, therefore the earth, in her yearly revolu- 

 tion around his center, performs more than a complete revolution 

 of one primary circle in space; and consequently, in a series of 

 revolutions round the sun, gains one complete year relatively to 

 that center around which the sun revolves. It is a demonstrable 

 truth that every period of time marked by the revolution of the 

 heavenly bodies is greater than one primary circle, for the reason 

 that each and all of the heavenly bodies are themselves also in 

 motion. Our theory then is seen to be that the magnetic attraction 

 to that high center is the force which directs the needle to the 

 poie — that our revolution around that center is the cause of 

 the revolution of the so-called magnetic pole, Avhich last is again the 

 cause of the variations of the compass. The reasons given for 



tion. It may he caused by tho sun's attraction, be being sometimes east and sometimes 

 ■west of us; but the return of the needle during the night to its position of the previous 

 day, is too gradual to be caused by temperature alone. The yearly revolution, when traced 

 out, will, I think, explain satisfactorily why the motion round the great circle is sometimes 

 faster and sometimes almost stationarj', or "even slightly retrograde. 



