Chase,] 6i^ [April 15, 



mately estimating the disturbing influence of Mercury ; and in a year all the 

 planetary regions of the spectrum might be studied. The relations of the 

 C line to Saturn and to hydrogen may, perhaps, be found specially inter- 

 esting. 



39. "Basic Lines." 



with sethereal and cosmical nodes. 



Harmonics. Basic Lines. 



4* X io = 4315.6 4215 



(4* + 7^) X Xo = 5022.4 5017 



(4* + 72 4- 3^) X ;.o — 5110.Q 5170 



(4* + ji + 32 + 2^) X ;.o = 5236.5 5235 



(4 *+ 8^) X ^ = 5269.4 5269 



(4* + 82 + 32) X Ao = 5417.6 5416 



42 X 52 X ^ = 6586.8 6567 



The third and fifth "basic lines" are double. Lockyer gives for the 

 third, 63, bi ; for the fifth, 5268, 5269. Gibbs gives 5177 for the length of 

 the b line ; Angstrom's table gives 5167, 5164, for 63, b^. The mean, 

 according to Gibbs' measurements, is 5170. The three hydrogen lines, 

 a, 5, ^, correspond nearly with the Fraunhofer lines, C, F, and G, but 

 Angstrom makes the wave-length of the y line 4340. The three lines 

 maybe expressed by 4^ x 5^ x /lo = 6586.8; (4* -j- 5 X 2^) X Ao = 4873.7; 

 (4* + 33) X /lo = 4346.7. 



40. Chemical Spectra. 



Soon after my announcement of the accordance between the simple har- 

 monic wave-lengths in the solar spectrum and the exponential harmonic 

 loci in the solar system, I showed * that the law of harmonic vibration also 

 extends to the spectra of chemical elements. The following accordances 

 are especially interesting in relation to the basic lines: 



Normal Differences. Observed. 



Hg., 5438.0+ 2 ^ = 5460.9 5428.0 5461.3 



Pb., 4390.7 -f 6 ;.o== 5378.7 4390.7 5377.1 



Li., 4599.3 + 12 /lo = 4796.9 4599.3 4794.8 



Rh., Ir. 5305.2-1- 9 /« = 5453.6 5305.2 5454.4 



Cu., 5292.7 H- 80 Ao z= 5788.7 5293.0 5786.7 



As., 5335.5 + 51 ^^ = 6174.7 5335.5 6175.4 



5787.3 + 30 /lo = 6116.6 5787.3 6116.7 

 Zn., 4733.3 4- 84 ;.o = 6106.4 4733.5 6106.4 



6106.4 + 16 /lo = 6369.9 6106.4 6369.9 



The tendency to composite and pendulum multiples of the fundamental 

 line is also shown here ; 2, 2 x 3, 2^ x 3, 3^, 3 x 3 x 5, 3 x (2* -|- 1), 3^ x 5, 

 32 X 3 X 7, 3*. The Arsenic line, 5335.5, is 2^ x 3* x /lo ; in the two 



♦lb, xvii, 297-301. 



