Proceeding's of the American Academy of Arts and Sciences. 

 Vol. XXXVI. No. 7. — August, 1900. 



CONTRIBUTIONS FROM THE HARVARD MINERALOGICAL 



MUSEUM. 



YIIL — ON HARDTSTONITE AND A ZING SCHEFFERITE 

 FROM FRANKLIN FURNACE, N. J. 



By John E. Wolff. 



WITH A NOTE ON THE OPTICAL CONSTANTS OF THE 



SCHEFFERITE. 



By Dr. G. Melczek. 



