534 Transactions. — Miscellaneous. 



equinoxes. I also see that the preponderance of the Northern 

 Hemisphere affects the question in a somewhat different way 

 from that suggested by Major- General Dray son, and which in 

 my address I accepted. During summer in the Northern 

 Hemisphere the pull on the equatorial protuberance tending 

 to bring the plane of the equator into coincidence with that of 

 the ecliptic will be directly opposed by the extra pull on the 

 Northern Hemisphere. During winter it will be aided, but in 

 a lesser degree, the north pole being turned away from the sun 

 instead of towards it. During autumn and spring the effect 

 produced by the equatorial protuberance is reduced, becoming 

 zero at the equinoxes. The tendency produced by the north- 

 ern preponderance will be to draw the north pole towards the 

 sun — i.e., towards the north during autumn, towards bhe south 

 during spring. These two tendencies, being equal, would 

 eventually balance one another. The total result, then, must 

 be to diminish the effect of the equatorial protuberance, and 

 therefore to increase the time required for a complete second- 

 ary rotation or precession of the equinoxes. Whether the 

 northern preponderance has any effect in determining the 

 axis of the second rotation I am not prepared to say ; but it 

 seems to me probable that it has such an influence, and that 

 variations in the direction of the axis may have taken place 

 in past periods of the world's history, as Major-General 

 Drayson suggests, caused by the great upheavals and sub- 

 mergences of land which geology records. The working-out 

 of the problem requires the use of the highest branches of 

 mathematics, with which I am not familiar ; but it has been 

 refei^red to a distinguished mathematician in England. Mean- 

 while, the facts of the second rotation of the earth on the axis 

 and in the period discovered by Major-General Drayson, with 

 all the remarkable results of the discovery, remain uncontro- 

 verted. Quite recently these facts have been verified and 

 established by Admiral De Horsey in a totally independent 

 and original process of investigation and calculation. 



