Deoember 18, 1903.] 



SCIENCE. 



775 



specimens in various parts of the collection 

 as being from Franklin, N. J. 



3. The gangue of all minerals from 

 Pajsberg and Langban, Sweden, also 

 showed this peculiar red glow; the lime- 

 stone strikingly like the calcite from Frank- 

 lin, N. J. 



fliuii'esced with radium; those tested with 

 magnesium light phosphoresced. 



5. Ilydro-zincitc, from Algiers, showed a 

 remarkable fluorescence, bluish in color, 

 different from anything in the collection. 



6. Autunite and another uranium min- 

 eral, from Mitchell County, N. C, 



Column 1 is Madame Curie's list of rare minerals; 2 is K.-B. ultra-violet rays; 3, Roentgen rays. 

 With one exception, neither of the latter shows any action. 



4. All the minerals from Borax Lake, 

 California— the colemanite, hanksite, glau- 

 bcrite, iddingsite and many others— with- 

 out exception phosphoresced with ultra- 

 violet rays. The briefest exposure caused 

 them to glow and to retain this lumines- 

 cence for a considerable time; but none 

 of these minerals either phosphoresced or 



fluoresced wonderfully, while foreign 

 specimens of the same species did not. 

 Autunite appears to have two minerals 

 present with it; one an orange and the 

 other a lemon yellow; one pulverulent 

 and the other in slight tabular crys- 

 tals. The striking fluorescence obtained 

 with ultra-violet rays was not produced 



