366 _ G, Hinrichs on Spectral Lines. 
We cannot here go into any detail as to the relation of these — 
formule to the numerical relations discovered by Carey Lea, 
Dumas and others; we hope soon to be enabled to publish our 
labors on the constitution of the elements. Neither can we here 
discuss these formule in the sense of the mechanics of atoms 
deducing the physical and chemical properties of the elements 
from these formule; these interesting relations also we must 
delay till some future, but I hope not a very distant, time. Nor 
is this the place to discuss the few slight device noticed. 
‘Our aim here i is to make use of these our old formule in spectral 
analysis. 
First, seca we notice that the alkaline-earth metals are quad- 
ratic, so that their 3 shots are the result of two systems only of 
lines. Further, having a common base (2), they must show one 
set of differences, either absolutely or nearly equal—which, until 
_ we havean analytical investigation hereof, or fuller experimental 
results, we cannot decide. But this is precisely what has been 
found in §22, where the intervals were found respectively to be 
MagncnaMl y 23.3... PG ages 000000157 mm. 
Calcium evewee eee es 160 
Strontitiin 2c ve fee ee 161 
SMGWl sv saect seeker ee 163 
We might now discuss the occurrence of the dimension-figures 
of the atoms in the corresponding spectra as intervals ; suc for 
magnesium 2 and 3, for calcium 2 and 5, ete. Such coinciden- 
ces are pretty numerous, but a fuller stock of still more reliable 
measurements will be required for the metallic spectra 
For the chlorine group we have the following dimension n, and 
distance d of lines, according to the given tables. 
n d n.d 
Chlorine, 4 47 188 
Bromine, 9 25 225 
lodine, 14 8 112 
Then by se a Sep the interval 8 for iodine we get 14x 16=224; 
or the distance of the lines is nearly inversely proportional to the 
atomic eneusien 
The other dimension of this group is 8, and is fairly repre- 
sented in the intervals. Thus we have in the spectrum of todine, 
neglecting the two extremes which are not necessarily complete, 
the intervals (see § 7) 
21=3X7 : 
638-8 <21=-3 X 8X7 
23+4-4=—-27=3X9 =3X3X3 
where the dimensions 3 of the base 3? is fully a The 
extreme intervals are 77=3 x26 less 1, and 29=3 X10 less 1. 
oy = 
pea NE ei eS 
