Limit of transparency of thin 

 plates of fluorite. 28 



Estimated limit of waves pho- 

 tographed by Schumann, de- 

 rived from Hydrogen spectrum. 29 



900 Ionization of air begins. 



750 Observed by Lyman in Spec- 



600 trum of Helium. 



UNKNOWN RADIATIONS— NINE OCTAVES 



1 SOOA.U. 



2 250 



3 125 



4 62.5 Unknown 



5 31.25 Radiations. 



6 15.62 



7 7.81 



8 3.90 



9 ■ 1.95 



X RAYS— X OCTAVES 



1.66 A.U 

 1 1.5 



0.976 - X Rays from Nickel. 



0.619 " " " Rhodium. 



0.614 " " " Palladium. 



0.58 " " " Rhodium 



0.51 

 0.488 

 0.475 

 Reference INDEX TO REFERENCES 



Numbers. Page. 



1 Waves and Ripples (Fleming) (1902) 261 



2 

 3 



4 Spectrography (Ramsay) (1905) 226 



5 Waves and Ripples (Fleming) (1902) 258 



6 



7 Light for Students (Edvi^in Edser) (1902) 347 



8 " " " 3^7 



9 Spectrography (Ramsay) 234 



10 Light Visible and Invisible (S. P. Thompson) (1910) 190 



11 Light for Students (Edwin Edser) (1902) 34' 



12 Spectrography 234 



13 Physical Review, Dec. 1910 (H. E. Ives) 638 



14 Spectrum Analysis (Landauer) (1907) 61 



15 Light Visible and Invisible (1910) 72 



16 Physical Review, Vol. XXXII. June 1911 



17 Light Visible and Invisible (1910) 72 



18 " " " " 342 



19 " " " " 164 



20 Spectrography 



21 Light Visible and Invisible (1910) 164 



22 Spectrography 256 



23 " 256 



24 Light Visible and Invisible (1910) :.. 191 



25 " " " " 191 



26 " " " " 191 



27 Photo Electricity (Dr. H. Stanley Allen) 110 



28 Spectrography 25S 



29 " 257-267 



30 Science NS Vol. XL. No. 1040 800 



37 



