ANALYSIS OF THE SOUNDINGS TAKEN BY THE "AMRA." 25 



slope both of Haddummati and Suvadiva is very abrupt. We ran into nine 

 hundred fathoms at from three to four miles from the edges of the group. 



Soundings across the Equatorial Channel, from Suvadiva to Addu, via 

 Fua Mulaku (PI. 8c, fig. 23). 



Six miles south by east from the normal, across Gan Channel, we obtained 

 ten hundred and forty fathoms (No. 29), with a bottom consisting of fine 

 greenish coral sand and Globigerinae. Twenty-one miles from the same 

 starting-point we sounded in twelve hundred and sixty-two fathoms (No. 30), 

 with a bottom of greenish Globigerina ooze. Thirty-one miles from our 

 starting-point, and about three and one-half miles from Fua Mulaku, we 

 sounded in twelve hundred and ninety-two fathoms (No. 31), the bottom 

 consisting of fine greenish coral sand mixed with broken shells. Fua 

 Mulaku ' rises quite steeply from the bottom of the channel, separating 

 Suvadiva and Addu. 



On our way north from Addu we made a sounding about halfway from 

 Addu to Fua Mulaku in ten hundred and forty-eight fathoms (No. 35), with 

 a bottom consisting of greenish Globigerina sand. With the exception of 

 the manganese nodule patch the bottom of the Equatorial and of the One 

 and half degree Channel is oceanic. It is covered with Globigerina sand. 

 Coral sand and Pteropod bottom are only found on the upper slopes, in close 

 proximity to Suvadiva and Addu. 



The two soundings of ten hundred and twenty-seven and twelve hundred 

 and forty-three fathoms, indicated on the chart to the west of our sound- 

 ings, and of thirteen hundred and twenty-nine fathoms to the east, seem 

 to indicate the existence of a broad plateau of comparatively uniform depth 

 on both sides of the line we ran. 



Line south of Addu (PI. 8c, fig. 21). 



We hoped to extend a line of soundings from Addu far enough south to 

 show how far its slope extended, and how far the Maldivian ridge or plateau 

 was connected with the Chagos Archipelago (see p. 6). Unfortunately we 



1 It was unfortunately too rough for us to attempt a landing on Fua Mulaku, both on our way to 

 and from Addu. 



