B82 ANNUAL REPORT SMITHSONIAN INSTITUTION, 1912. 



The knowledge of gems constitutes only a small part of miner- 

 alogical questions which are presented in Madagascar. Its extinct 

 volcanoes, its rocks and their minerals, its ores, their composition, 

 their mutual relations, their genesis, their modes of alteration deserve 

 in the highest degree the attention of men of science. 



Fifteen years of work on these materials of all kinds accumulated 

 in my laboratory of the museum through the devotion and intelligent 

 curiosity of explorers, officers, administrators, of colonists, prospec- 

 tors, had very often made me dream of the Great Isle. 



This dream has become a reality. This has not in the least dis- 

 appointed the hopes that had been born in my mind. 



