88 Director's Atniual Report. 



nature, but the grinding and sorting process of the waves is clearly 

 seen ; the larger and rougher materials remaining in the upper 

 beaches, while shingle and coarse sand form the lower ones. 



In the middle of the island along this side the highest point is 

 not to exceed fort}- feet, while at the southeast point an elevation 

 of sixtj-'five or seventy feet is attained. Turning to the interior of 

 the island we found the surface to be, generally speaking, quite 

 level, though the eastern half was broken up into minor surface 

 ■ irregularities. A little to the northwest of the centre were four 

 separate deposits of loose black alluvial soil, which undoubtedly 

 mark the location of as many dry lagoons. 



Generally speaking the island has been built up about these 

 spots as a centre. The surfaces of these old lagoons are lower than 

 the surrounding land, but still are in the neighborhood of twenty 

 feet above sea level.' The western and northwestern portion of the 

 island is made up of sand more or less mixed with humus. The 

 eastern and southeastern portion is composed of coarse blocks of 

 coral, coral shingle, huge coral boulders, and a great quantity ol 

 coral branches the prongs of which are ofttimes scarcely broken. 

 A hundred and fifty 3-ards from the coast line on every side the 

 whole surface of the island is heavily wooded, excepting that 

 scattered about here and there are to be found irregular patches, 

 from a few rods to a few acres in extent, which are entirely desti- 

 tute of trees and shrubs (Fig. 4), for which the composition of the 

 ground offers no solution. 



The extent of the coast line is a little over four miles, while 

 the area of the island (estimated) is about 740 acres. A somewhat 

 hasty surve}' of the island was made, from which field data I was 

 able to draw the map given on another page. The following table 



3 Mr. Sedgwick, in earning on the investigations of the Guano Company, made a number 

 of excavations in various parts of the island, but especially in the bottoms of these old 

 lagoons, which were now overgrown with thick grass, shrubs and trees, over which towered 

 fine coconuts of great age. In these depressions e.xist varying conditions in the under strata, 

 though the surface is uniformly composed of alluvial deposits varying in thickness from 

 eight to fourteen inches. Underneath this, in the coconut patch, were found coral sand and 

 earth from six to ten inches, then a layer of coral sand with pebbles, and occasionally .solid 

 base-forming coral in a slab, under which was found broken coral. In the two other larger 

 alluvial patches beneath the black earth was light clay-colored mud composed of fine par" 

 tides of coral, and below this were larger pieces of coral as tar down as the excavations were 

 carried, which was from six to eight feet. The investigations of the Chemist were not nearly 

 as complete or as conclusive as it had been planned to make them. A limited quantity of 

 guano was found which gave a test of 70 per cent, phosphate of lime ; but the great majority 

 of the samples secured were not .so flattering. 



