172 A Notation for Zeeman Patterns. 



for all metals. Thus for Tl D ]2 it is 5 | 3^.6.10, for Ca and 

 Sr 5 | 6, for Ba 5 | 3.6.10; and it would appear that the 

 typical form is 5 | 3.6.10, but that some of the perpendicular 

 vibrations (3.6.10) maybe too faint to be observed. In 

 Mg — which does not exhibit satellites — the line keeps to 

 the D n type. In others— e. g. in the Cu line 5700 — the pattern 

 is 5 | 3.6^.10. It belongs to a doublet of the D type which 

 shows no satellites, and the pattern seems to be that of a 

 combined D n and D 12 . The corresponding doublets in Ag 

 and Au show satellites, and in these each component exhibits 

 the normal pattern for each. 



Triplets. 



S So s 



0.3 | 6.9.12, 3 | 9.12, | 12. 



The remark above as to the absence of a component being 

 apparent only is well illustrated by the case of HgS t and HgS 2 . 

 Thus indicating intensities by numbers in brackets after the 

 figure giving the displacement, we have for the first three 

 triplets : — 



Sx(l). 8,(2). S x (8). 



0(4). 3(3) | 6(4).9(5).12(3), 0(2).3(1) | 6(2).9(1).12(3), 0(1) | 6(1). 



S 2 (l). 8,(2). S 2 (3). 



3(4) | 9(4). 12(5), 3(1) | 9(2).12(2), ? | 9. 



Judging from the rate of decay of intensity with in- 

 creasing order, however, we might have expected the com- 

 ponent 12 to be the last to go in Si (3). 



D 13 . D i2 . D u . D 22 . B 21 . D 31 . 



? 4 | 7, | 7, ? | 6, | 3. 



The satellite patterns, as in the case of the doublet series, 

 are not uniform. Thus for D ]g , Ca has | 6-J-, Sr | 15, 

 Cd 4 | 10, Hg 0.6 | 3.9.15. It is interesting to note that 

 the abnormality lor Sr and Cd is shown also in their deviation 

 from the rule that the mantissas of the denominators of D 13 (2) 

 are multiples of A 2 — in these elements the multiple occurring 

 in D 12 and D n instead*. For D 22 the normal type is 

 probably 6 j 3-9 Ca and Zn give 6 | 6, Sr | 9, Cd and 

 Hg 6 | 3.9. Hg D(2) has very complicated and abnormal 

 patterns, and as is known the satellites themselves have 



* Phil. Trans. A. ccxiii. p. 374 (1913). 



