THE AUSTRALIAN GREAT BARRIER REEF. loi 



lightning-fused aggregations of siliceous sand ma}- be obtained in tolerable abundance. Mr. 

 Darwin, in his " Voyage of the Beagle," records the occurrence of similar structures among sand- 

 hillocks on the shores of the La Plata, near Maldonado. Each Sandy Island specimen consists 

 tor the most part of a central solid or tubular axial core, several feet in length, and three or 

 four millimetres in diameter, around which subtend, in some instances, irregularly granular, and 

 in others thin crest-like, ridges, which may measure three or four centimetres in width. In the 

 last-named variety the crests, or ridges, while presenting no absolutely definite plan of arrange- 

 ment, commonly number three or four, and diverge at equal angles with respect to one another, 

 and to their centre. 



Great Sandy Island is the proud possessor of a story of its own particular sea-serpent, 

 which, if space permits, may find an appropriate place in the chapter on " Potentialities." 

 Its introduction at the present juncture might prove inimical to the calm consideration of 

 weightier scientific problems. 



Bidding adieu to Break-sea Spit and its concourse of troubled waters, it takes one but a 

 few hours of either sailing or steaming, north, to arrive at Lady Elliot Island. This island, 

 with the surrounding reefs, represents, as previously related, the most southern islet or reef of 

 the Barrier sj'stem ; constituting, in point of fact, a sort of outlying bastion of that stupendous 

 coral-constructed fortification which, with irregularly-recurring gaps, stretches from this point to 

 within a few degrees short of the equator. The distance of Lady Elliot Island from Break- 

 sea Spit is thirty-two nautical miles, and that between it and the next islet of the Capricorn- 

 cum-Bunker group, just ten miles less. From Round Hill, the nearest point, due west, 

 of the Queensland mainland, it is distant fifty miles, and from the outer edge of the 

 shallow soundings, of from fifteen to thirty fathoms, which characterise the greater portion 

 of the channels and water-areas that intervene between the outer reefs and the mainland, 

 only two miles. Beyond this point, due east, over two hundred fathoms without bottom, is, 

 as indicated in the Admiralty charts, immediately reached. Lady Elliot Island, when visited 

 by Professor Jukes in the year 1843, ^^ described and illustrated by him in the "Voyage of 

 the Fly," was the abode of innumerable sea fowl. Now, it is the site of a first-class light- 

 house, which, in conjunction with that on Sandy Cape, Great Sandy Island, illumines the 

 broad entrance, via Curtis Channel, to the inner route along the Queensland coast to Torres 

 Strait. 



The physical aspect of Lady Elliot Island, as embodied in Mr. Jukes' description, remains, 

 with the exception of the destruction and removal of the greater portion of the trees, unchanged 

 at the present day. His account of it may, therefore, be reproduced verbatim. Writing of 

 it as having given him his first acquaintance with a coral island, he says : — 



" The beach was composed of coarse fragments of worn corals and shells, bleached by the 

 weather. At the back of it a ndge of the same materials, four or five feet high and as many 



