CONTENTS. XV 
art Fourth. 
HISTORICAL, THEORETICAL, AND PRACTICAL 
CONSIDERATIONS, 
CHAPTER PAGE 
TI. Hisroricat Nores - ? : A 2 ay (7 | 
If. THrory ? P 4 ; : 3 \ ci, RSL 
IIT. Practicat CONSIDERATIONS. f , 7 . 196 
APPENDIX. 
List OF PRINCIPAL WORKS THAT HAVE CONTRIBUTED 
TO OUR PRESENT KNOWLEDGE OF PHOSPHORESCENCE. 203 
