EFFECT OF PEESSUEE UPON AEC SPECTEA. NICKEL. 



231 



the cloud of dots above them, and that we draw the above conclusion from 

 the fact that the group of dots representing high values of the displacement in 



Diagram 6. Frequency distribution of spectrum Hues. 



Fig. i. 



5*1 

 ml 



74 68 106 



65 I03I6S 



'! 75 81 



63 l 6f 77 



OS S/ 50 4 



<8 *5 1 



Fiq.2. 



44 30 41 11 I65 

 fr 58 15 39 19 87! 



51 15 36 17 461T1 

 18 3.615 37 16 39 1C I 



I' 

 HI 



Ja 



74 



fet 9i ,l/ 6 



64 65 ioa 7? 



1 68 



55 51 t5 45 46 



46 40 50 41 At 



I 4* 56 36 i9 31 i< 



ISs 25 JOS? 7 2 _ 



fii is as is is e 16 is 5 







Fig. 1. According to values of the displacement per atmosphere. 



displacement per atmosphere 



wave-length 



displacement per atmosphere 

 " (wave-length)-' 



displacement per atmosphere 

 " " " (wave-length) 3 



(Eeadings at 10 atmospheres excluded.) 

 [Numbers overlined are of doubtful accuracy. The horizontal scale is proportionate, not absolute.] 



Diagram 6, figs. 1 to 4, is more compact when the displacements are assumed to depend 

 upon a high value of the wave-length. The group might be more compact still if sen 



2 H 2 



