266 PLANTS, SEEDS, AND CURRENTS 



of the Turks Islands is based on Captain Owen's survey of 1830, 

 with additions to 1845 and corrections to 1898 ; whilst the French 

 chart is emended from observations made in 1770 in an English 

 survey ; so that the period for comparison is limited to sixty years. 

 However, as will be shown below, the changes that can be estab- 

 lished are all on the side of " gain." The reclaiming process is 

 indicated : — 



(a) By the shoaling of the Bank. — Whether we referred to the 

 French chart or to the later chart, we should be equally correct in 

 saying that the bank from which the Turks Islands rise is covered 

 by from ten to eleven fathoms of water in the deeper parts. But 

 more than eighty years have elapsed since the last survey, and it is 

 evident that the whole bank is shoaling through the growth of coral 

 and the accumulation of reef debris. Sandbanks are forming in 

 the shallows and are endeavouring to give rise to new islands. One 

 such islet, known as Lesser Sand Cay, lies half-way between Grand 

 Turk and Cotton Cay. Though well exposed at low-water, it is 

 ever shifting its site and changing its form. At times vegetation, 

 derived from drift seeds, begins to appear on its surface ; but before 

 long this is washed away by the waves. When I knew it in the early 

 part of 1911, it was a bare bank of sand not 100 yards in length. 

 Yet in time a permanent islet will be established, and a century 

 hence it will be well stocked with littoral plants. 



(b) By the throwing up of Protective Beaches and Sandbanks around 

 and between the nuclei of JEolian Sandstone. — Yet Nature has other 

 ways of reclaiming land from the sea on the bank. After the waves 

 have been battering for ages one of these islands of seolian sand- 

 stone, she often sets herself to work to save the pieces through the 

 growth of corals and the heaping up of sand and other reef debris. 

 Let us take the case of Greater Sand Cay, which is about one and a 

 half miles in length and elevated some forty feet above the sea. 

 We can read its history as we approach it from the northward. In 

 the distance it appears as a group of four islets. But as we get 

 nearer low connecting strips of land rise above the horizon, and we 

 discover that the four islets, as they seemed, form the hummocks, 

 or low, mound-like hills, of a single island. The hummocks are 

 made of the seolian sandstone, and the low necks that unite them 

 are banks of sand. Here it is evident that a long strip of land of 

 aeolian rock was first broken up by the action of the sea. But in 

 later times, whilst the waves were wearing away the islets, the water 

 was shoaling around. Ultimately the energy of the waves was 

 chiefly occupied in throwing up protecting beaches and in joining 

 the islets by sandbanks. In this way the remains of the original 

 island have been preserved, and doubtless the present island will 

 continue to increase in extent. The process of joining up the islets 

 has evidently been in operation in relatively recent times. In the 

 French chart (1753-70) the northern third is represented as separated 

 from the rest of the island by a channel 250 or 300 yards wide and 

 two feet deep. The extensive shoal or patch of reef that runs north 

 from this island seems to be in much the same condition now as it 

 was a century and a half ago, except that there appears to have 



