PR. W. GEOFFREY DUFFIELD ON THE 

 these 



, ~ the natu,, of the hroade^ of the Kn. that have 

 been observed in this research :- 



TABLE III. 



6. Tfie Displacement of the Lines: (1) The Measurement of the Photographs. 

 This was conducted as in the case of the silver lines (cf. p. 40 supra). Twelve 

 settings were made upon each line upon each plate, six with the red to the right and 

 then six with the red to the left. The whole series was then repeated, so that at 

 least 24 readings of the displacement of each line were obtained. 



(2) Description of Table of Displacements. Table IV. gives in thousandths of an 

 Angstrom unit the value of the displacement of each line at the pressure stated at 

 the top of each column. The first column contains a list of the arbitrary letters 

 assigned to the different lines. The second column gives the wave-lengths of the 

 lines according to the tables of KAYSER and RUNGE and EDER and VALENTA. The 

 subsequent columns show the displacements. The pressures are the excess above one 



