108 NOMOS. 



In the first place, then, let us endeavour to follow the 

 movements of the earth, and in order to 



Application , . , , . , . , 



of the law of this let us assume two things which are 



n t very problematical. Let us assume 

 ofSe n mo- n tnat currents of electricity (we use the 

 laTth fthe term electricity in that wider sense which 



has been explained before) surround the 

 earth in a direction which is parallel to the plane of 

 the ecliptic ; let us assume that similar currents pro- 

 ceed from the sun to the earth and converge upon 

 the part which is nearest to the sun; and we may 

 soon see that the earth must move around the sun, 

 and that she must rotate upon her axis as well as 

 move onwards in her orbit. Nor are these assump- 

 tions at all unwarrantable. The first is not unwar- 

 rantable, because the manner in which the magnetic 

 needle is found to lie across the plane of the ecliptic 

 may be taken as an almost certain proof that elec- 

 trical currents travel in this plane. Nor is the second 

 assumption unwarrantable, for we may appeal to the 

 solar ray, which presents all the signs of the current, 

 as evidence, not only that a current flows from the 

 sun, but that it converges to the parts more imme- 

 diately under the sun. For may not the greater 

 power of the solar rays at noontide be in part at least 

 the consequence of such convergence ? 



Let E and s be transverse sections of the Earth 

 and Sun in the plane of the ecliptic, and let the ar- 

 rows represent the currents of which we have just 

 spoken, and it follows from what has been explained 

 already (p. 72), that the mutual reaction of the two 

 sets of currents will give E that movement which we 



