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APPENDIX 



for the middle of Salt Cay and the middle of Greater Sand Cay. 

 The error in the longitude, as compared with the Admiralty chart, 

 is about forty minutes on the minus side, and that of the latitude 

 ranges from almost nothing to two miles. Except in the case of 

 Grand Turk, the dimensions of the larger islands as given in both 

 charts do not differ greatly — the length of Grand Turk in the French 

 chart being three and three-quarter miles instead of nearly five and 

 a half miles as in the later chart. Unfortunately the period for the 

 valid comparison of the two charts is limited to only sixty years, 

 namely, between 1770 and 1830, since the additions are not dis- 

 criminated in either case. 



The soundings in the French chart, though far fewer than in the 

 Admiralty chart, are fairly well distributed over the bank. The 

 comparison, as far as it goes, indicates that the maximum depths 

 over the bank were the same at the time of the French survey as 

 they were during the English survey. But the depths were more 

 uniform; and evidently the numerous shoals that now exist in 

 different localities between the islands, as between Grand Turk and 

 Cotton Cay, were not charted by the early surveyors. The limits of 

 the bank are imperfectly determined in the French chart; but one 

 or two areas lend themselves for comparison. All the area of the 

 bank lying south and east of a line drawn from Greater Sand Cay 

 through Salt and Cotton Cays to Pear Cay, and thence north-east to 

 the edge of the bank, displays a uniform depth in the French chart 

 of nine or ten fathoms. This is in a general sense the depth-condition 

 exhibited in the Admiralty chart over the greater part of this area, 

 except amongst the cays between Salt Cay and Toney Rock. Here 

 soundings of seven and eight fathoms prevail towards the edge of 

 the bank, and further in amongst the cays numerous shoal patches 

 covered by less than three fathoms of water exist, the prevailing 

 intervening depths being about five fathoms. 



Considerable changes seem also to have occurred in the area 

 between Cotton Cay and Grand Turk. Here the sea is so beset with 

 shoals and reefs that, as I know from my own experience, navigation 

 at night is dangerous. In the French chart it is credited with a 

 uniform depth of three and four fathoms, three in the northern half 

 and four in the southern half of the area. In the Admiralty chart, 

 although maximum depths of three fathoms in the northern third 

 and of four and five fathoms in the southern two-thirds are indicated, 

 numerous shoals, often with rocks awash, are also marked. Reef- 

 growth has evidently been active in these waters since the time of 

 the French survey, and it is probable that Lesser Sand Cay, a con- 

 spicuous sandbank midway between Grand Turk and Cotton Cay, 

 on which vegetation at times gains a hold, did not then exist. 



With reference to the changes in the islands indicated by a com- 

 parison of the two charts, the most noticeable one is the filling up 

 of a channel two feet deep, which in 1753-70 cut off the northern 

 third of Greater Sand Cay. In Captain Owen's chart the island 

 appears to consist of two parts connected by sandbanks that are 

 covered at high-water. But it may be that this was its condition 

 in 1898, when the last important additions were made. At the 



