THE MALDIVES 383 



On his return to America, Agassiz completed his pre- 

 parations for an expedition to the Maldives, a curious 

 group of composite atolls which lie about four hundred 

 miles to the southwestward of Ceylon. Previous to 

 his visit, there had been two memorable expeditions 

 to these islands. In 1831-36, Commander Moresby 

 made a survey of most of the group, upon which 

 the Admiralty Charts are based. The accuracy of this 

 work is marvelous when it is remembered that it was 

 done in the days of handlines, row-boats and sailing 

 vessels. The other explorer, Dr. J. Stanley Gardiner, 

 had lately returned from a prolonged study of the 

 group, mostly accomplished in a small sailing boat; but 

 the results of this expedition had not yet been pub- 

 lished. 



Darwin, who never visited the Maldives, considered 

 their peculiar formation due to the disintegration of 

 ordinary atolls. Agassiz had always intended, after fin- 

 ishing his explorations of the atoll and coral regions of 

 the Pacific, to make an expedition to these islands, 

 especially as they were the only great group of atolls 

 he had not visited. For this purpose he chartered the 

 steamer Amra of the British India Steam Navigation 

 Company. The vessel was equipped with a Lucas sound- 

 ing machine, built especially for the voyage, a modifica- 

 tion of the type used by the English cable companies, 

 which Agassiz found simpler and easier to handle than 

 the Sigsbee machine he had used on his previous expe- 

 ditions. She was also furnished with a Bacon winch and 

 a drum larffe enoug-h to hold eigdit hundred fathoms of 

 wire dredging rope. This equipment was to be used for 

 deep towing, and such few hauls of the dredge as there 

 might be time to make. As usual, the minutest details of 



