Chase.] '^ ♦ O ^jan, 19, 



335, The Neptuno-Vranian Belt. 



All tlie proposed forms of the nebular hypothesis seem to require evi- 

 dences of retrograde motion, such as are shown by the outer planets of 

 our system. The successive harmonic influences of central condensation, 

 conversion of orbital into rotary motion, incipient projection and incipient 

 subsidence are shown by the proportions which vi^ere given in Note 315. 

 If we take the oscillatory estimate, TOq = (3 X 3 x 4)* m,-^, instead of the 

 estimate in Note 313, we get m^ = 336.56?«j = 193T9mg ; p^ =19.138^3. 

 Newcomb's mass estimates are m^ = (33600 ± 100)mj = (19380 ± 70)7Wg. 

 The observed value of p., is 19.184^3, which is about \ of one per cent, 

 greater than the harmonic value. 



326. Terrestrial Ma/jnetlc Vis Viva. 



Equation (1) of Note 91 may be modified by regarding i\ as a mean 

 proportional between Earth's mean orbital velocity and the velocity of 

 light, and substituting the mass of the Telluric system, m^, for Earth's 

 mass. "We then have, 



m^v^ : Vfi^v^ : : vn^^ : m-^is^, 

 substituting v^ = p^ h- 497.837 ; u, = 3;r/53 -^ 31558149 ; m^ = 1047.879^5 *' 

 we get TO5 = 311.673m^; m^ = 326594m , which difiers by about ^ of one 

 per cent, from the magnetic estimate of Note 3 (327710). The identity of 

 the velocity of electro-magnetic disturbance {Maxwell, Electricity and 

 Magnetism, § 784) with the velocity of light, lends interest to this approxi- 

 mate coincidence. If we estimate m.^ = 81. 08a, these two values of m^ 

 give 



83.08 

 m„ = g^ ^g X 336594^3 = 330633^3 ; p^ = 93678000 miles. 



83.08 

 m„ = gj Qg X 337710»?3 = 331753^3 ; ^3 = 92783400 " 



The latter estimate of /j, difiers by less than -^^^^ of one per cent, from the 

 value which is indicated by centres of nodal oscillation (Note 91). 



327. Cosmic and Chemical Harmonic Motions. 



A harmony which involves considerations of the conversion of orbital 

 into rotary velocity, projectile vis viva, inertia of central condensation, 

 and energy of chemical combination, is shown in the proportion 



ra ■■ Po •• ■■ 9a •■ do ■■ ■■ rs' : h' 

 in which ^^ =• Earth's primitive locus of orbital projection, or secular 

 perilielion (Stockwell's estimate of secular eccentricity and the Brit. Naut. 

 Aim. estimate of Sun's apparent semi-diameter give ^^^ =200.385/0; 9a 

 = mutual gravitating acceleration of two equal particles at distance 7i ; g^ 

 = like acceleration at distance r^ ; 7i = theoretical height of socondarj' 

 centre of oscillation in explosive combination (Note 16). Solving the pro- 

 portion, we get, h = 279.943 miles ; ^3 = 93739000 miles ; m„ = 331380ffis. 



