1881.] ^'^ [Chase. 



copper lines which precede the two which I have given, the differences are 

 ^ of 30 ^0 and f of 30 ;.o. 



41. The Corona Line. 



In the communication* which led to my spectroscopic investigations, 

 Dr. Draper anticipated the probability of finding a key to "the 1474 K or 

 corona line." The following accordances may help towards a solution of 

 the mystery. The numbers in the right-hand column are the measure- 

 ments by Gibbs : 



Geometric Wave-lengths. Observed Wave-lengths. 



4311.9 X 1.0305" =: 6567.8 C 6566.7 



4311.9x1.0305^=5331.7 1474 K 5332.0 



4311.9 X 1.0305* = 4863.8 F 4865.3 



4311.9 X 1.0305" =4311.9 G 4310.3 



I have shownf that the harmonic densities of C and G are photodynami- 

 cally represented by the loci of Saturn and Venus. The corona line is a 



F C 

 mean proportional between and G. The exponential ratio of q; to j, 



is the same as the ratio of the mean moment of inertia of spherical rotation 



1474 K F 

 to the moment of superficial equatorial rotation. The ratio of — ^ to q^ 



is the same as the ratio of variation in an expanding or contracting nucleal 

 radius to the atmospheric radius. 



43, The Hydrogen Lines. 



Lockyer gives four hydrogen lines, C, F, y, h. The corresponding 

 geometric wave-lengths give the equations, Fh^ = y^ ; F^^ = C*h^ 



Geometric Wave-lengths. Angstrom's Wave-lengths. 



4099.5 X 1.01435^=' = 6560.3 C 6561.8 



4099.5 X 1.0143512 — 4863.9 F 4860.6 



4099.5 X 1.01435* =4339.9 y 4340. 



4099.5 X 1.014350 =4099.5 h 4101.3 



The most prominent line in the hydrogen spectrum, and the only one in 

 some cases, is F, which, as I have shown, is geometrically connected with 

 the corona line and with important cosmical nodes. 



43. Three Orders of Spectra. 



The two foregoing notes introduce a new order of spectra which seems 

 to be of a more elementary character than either of the two whicli I have 

 previously considered. The geometrical progression of wave-lengths sug- 

 gests a repetition of impulse, while the absence of some of the terms of the 

 progression indicates a want of complete homogeneity. 



The second order is that of the basic lines, which consists of a combina- 



* Proe. Am. Phil. Soc, xvii, 77. 

 t lb., xvii, 109-12. 



