THE CHEMICAL EXAMINATION OE THE MATERIAL8 FROM FUNAFUTI. 38SJ 



perfect dolomites are much rarer than " maguesian Kmestones," or rock.s in which 

 the proportion of magnesium carbonate present is insufficient for the con\'ersi()ii 

 of the whole rock into the double salt. 



From what has been said, it will be apparent that, wliile the investigations that 

 have been carried on upon the materials obtained in the vertical borings of Funafuti 

 and also on specimens obtained from upraised reefs in the Indian and Pacific Oceans, 

 show that the dolomitisation of coral reef-rock, first demonstrated by the researches 

 of Dana and Silliman, really takes place sporadically over very wide areas, the 

 exact conditions under which the operations occur still call for careful investigation 

 both by observation and experiment. 



The separation of the two carbonates from sea-water, to form double salts, niay be 

 possibly determined by complex relations, like those which van't Hoff and his 

 pupils have shown to govern the separation of the various salts which form the 

 Stassfurt deposits. It is satisfactory to know that this problem, as it afifects the two 

 carbonates, is now engaging the attention of a chemist, Dr. E. F. Armsteong, 

 who has already had considerable experience in this field of inquiry. 



