Modified Theory of Gravitation. 91 



32. From (46), (50) we have for the range o£ proportional 

 changes of volume o£ the aether, above and below mean 

 value, 



K=]F\/{-3p^)' ••■■■' (61) 



while for the rate (in ergs per second) at which wave-energy 

 is being propagated through any square centimetre of surface 

 whose plane is parallel to the wave-fronts, we must take the 

 product of the wave-energy per c.c. multiplied by the velocity 

 of propagation. Now throughout our purely progressive 

 wave-train the total energy per unit volume is B 2 /'2k, the 

 maximum value attained by the potential energy per unit 

 volume. Thus multiplying (47) bj' (51) the rate at which 

 wave-energy is being propagated, in ergs per second per 

 square centimetre, is found to be 



w/fc-^/fcg*} • • • W 



33. All the quantities with which we are now concerned 

 are expressed in terms of the following seven quantities : — 



(i.) G the Newtonian gravitation constant = 6*66 x 10~ 8 . 

 (ii.) K the motional constant, defined by (31) [2 X 10" 20 ]. 



(iii.) p the density of the aether [10 12 ]/ 



(iv.) E the constitutive energy per c.c. of the aether [10 33 ] . 



(v.) \ the wave-length of the primary disturbance [10 4 

 astronomical units = 1*5 x 10 17 cm.]. 



(vi.) fi the proportional increase of aetherial compres- 

 sibility arising from the presence of 1 gram of 

 atomic matter per c.c, as defined at the beginning 

 of §28 [20]. 



(vii.) $ a numeric defined by (48) [1]. 



Of these seven, only the first, the gravitation constant, is 

 known, the values indicated (in square brackets) for the 

 remaining six being merely conjectural. If no set of values 

 could be found which did not lead to demonstrably false 

 results, we should have-- to conclude that the theory in the 

 form here suggested was untenable. The considerations 

 leading to the choice of the values in question will be best 

 understood after the corresponding values of some related 

 quantities have been computed. The table (p. 92) gives in a 

 collected form the relations obtained in §§ 27-32. 



