Se TR IS ee ee ae ee ee ae) ee ee ee ee ee 
G. Hinrichs on Spectral Lines. 357 
hoff outside of the preceding groups. These give the following 
result: d=16, 
I K Ww D i Ww’ E 
Qe 18878 «50410 og «HD 0 
Sb 1627251856) yg | 51880 eS 
2 1443-5 58452, gg | RKO +8 
Se 10208 BES agg gg | BETO =F 
25 = 641-0 6721-2 67210 4-2 
f E 
: Se =: 2869°7 +s: 4322-0 7 43210 = -++-1-0. 
IL 5¢ = 2638-8 ~~ «= 4484-0 ai 4433-0 +10 
2c 18328 5041-0 5041-0 0-0 
5b §=:16272 = 51856 ag UI ere 
Il. 4b 15331 5 261°5 ‘ 52610 +5 
2b 8614435 = §345°2 4s 63450 + 2 
IV (last). 5d 12178 56010 +8 5601-0 0-0 
Sc 10293 = § 8563 13 58570 = 
Vv 894-9 6162-0 90g 61610 +10 
VI 2c 7201 6492-0 +4 6493-0 = —10 
2b 6410  6721°2 = 6721-0 +. 2 
The series of intervals admits of the following contractions: 
ea. Scape 8 ee : 
Sinneypiomeaiad? 
eg 10 1 As a 35 
45 9 10 16:48 54 
54 10 << 16 54 
64 ~*~: 16 54 
or 8 times 8 2 2 7 
Finally it must be noticed that this difference, d=16, accord- 
ing to this table may be taken an even number of times, up to 
, SO as to give a physieal interval; and 2d=382 is 5 times 6-4, 
the mean of the intervals deduced for the several groups 
hus we believe to have shown that the wave-lengths of Dits- 
ri in regard to the regular distribution of the dark lines in 
the ca m spectrum m fully confirm the laws enunciated in our 
pedlietioasy Ede mui? 
selrum. Having discussed the calcium spec- 
trum at éoneirile ap we may pass more lightly over the 
ium spectrum. As there are very few barium lines coinei- 
dent with those st by Ditscheiner it may be sufficient to 
multiply the difference between Kirchhoff’s numbers with the 
tangent or grade of the curve at the point considered (that is, 
the ratio between dW and dK) as taken from our — . 
Am. Jour. Sc1.—Szconp Serres, Vor. XLII, No. 126.—Nov. 
46 
