ADDU ATOLL. 



415 



Our impression was that they were closing up by lateral as well as bottom growth, while the 

 lagoon in the immediate vicinity is deepening, our anchorage, where 17 fathoms were marked, 

 being 20 f. The former presence of a velu opposite Mahuta, now opening into the lagoon, is 

 interesting. 



None of the lagoon islands in this vicinity nor to the W. are inhabited, and all are stated 

 by the natives to be washing away. Gula and Hibadu to the N. have much dead and fallen 

 timber. An unnamed island, marked in lat. 0° 37' N., has completely disappeared, save for a few 

 rocks on the centre of its shoal, covered at high tide. Such reefs as there are within the 

 lagoon extend generally in the direction of the currents, and mostly have precipitous slopes. 

 No marked growth in any was noticed except near the large W. passage in lat. 0° 45' N. On 

 the contrary Hibadu and Gula had practically no reefs opposite those shores where fallen 

 timber lay, showing that loss of land and reef was taking place almost simultaneously. The 

 large shoal opposite a passage in lat. 0° 41' N. appeared also to have broken up into five smaller 

 reef patches. 



XI. Addu Atoll (Fig. 109). 

 The most important changes in this atoll have already been dealt with in Appendix A, 



Huludu 



Fig. 109. Addu Atoll. The map is baaed on the Admiralty Chart, altered in accordance with the observations of the 

 Expedition. Mr Forster Cooper's soundings alone are marked. Scale 2 miles to 1 inch. (For changes compare 

 the Admiralty Chart on p. 150.) 



Section II. " The Formation of Lagoons." The land shows differences at either end of every 

 island, so that the atoll being small, we could get no even approximately fixed points for our 



