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only 93, instead of 97: and if, on the contrary, he has enlarged his distance on the original bearing, to make it answer to the latitude, the original distance could have been only 85 miles.

I have said before that Capt. Ritchie went no higher up the west side of the Great Andaman, than about the latitude of 12°. The remainder of that coast, as well as the passage through the islands at the north end of it, is from a MS. chart lent me by Mr. Dalrymple; and which carries with it the greatest appearance of truth, on a comparison of the south and south-west parts of the Great Andaman in this chart, with the same parts in the chart of Capt. Ritchie.

Barren Island, and the rock on the east of Duncan's Passage, are from the remarks of Capt. Justice in 1771.

ISLAND OF CEYLON.

It happens that the ordinary tracks of British ships, to and from Ceylon, and the coast of Coromandel, are not calculated for determining the relative positions of Point Pedro and Point Calymere, the approximating points of Ceylon and the continent of India. Hence it is, that we are so ill informed, not only of their true situations with respect to each other, but also with respect to the parallel of latitude under which Point Pedro is situated.

By my observations, Point Calymere (the southern extreme of Coromandel) lies in 10° 20′ latitude, and by inference from Madras, in longitude 79° 54′ 30′′. M. D'Apres places it 6 minutes more northwardly; and D'Anville 7 further south. The latitude of Point Pedro is also variously represented by the above geographers: I have taken it at 9° 52'.

In M. D'Apres I find the bearing and distance from Point Calymere to Point Pedro, to be

In D'Anville

In a MS. chart, no name

S 37° E

41 G. miles.

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I had an opportunity in 1764, of determining the position of Cow Island from Tondi, very nearly: I made it 10 G. miles west of Point Calymere, and 39 east of Tondi. Between Cow Island and Point Pedro, Van Keulen reckons 412, and D'Apres and D'Anville, 42 miles of easting. This will place Point Pedro 311⁄2 east of Point Calymere, or in longitude 80° 27'; and in bearing from Point Calymere E 43° 20' S; 42 G. miles distant. I have placed it in this situation, accordingly; as thinking it not liable to any great objection.

The figure of the island of Ceylon is variously represented by different geographers. Van Keulen makes it too narrow in the swelling part; that is, between Batacola and Columbo; as is pretty evident from the longitudes shewn by the time-keepers of some of the commanders of the East-India ships, and others. D'Anville and D'Apres in their maps of the island, agree much better with these observations.

Between the meridians of Calitoor and the east side of Ceylon in lat. 7° 40′, Van Keulen reckons the difference of longitude only

M. D'Anville

M. D'Apres

And by the time-keepers it is

1° 46'

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However, until a regular series of observations by time-keepers is made by the same person, all round the island, we must despair of seeing the true figure of it, unless its coasts were surveyed. The casual observations which we are in possession of, from different hands, will only afsist us in fixing certain points of it; which being done, the general figure of the island must at present be collected in the best manner it can be done, from the charts existing.

The following are the observations of longitude taken on the

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Dundrahead by Mr. Topping's observation (worked to Pondicherry in lon. 80°) is in lon. 80° 39′: I reckon Point de Galle 28′ west from Dundrahead, therefore it should be by this account in 80° 11'.

Mr. Topping observed the longitude of the Great Bassas also; so did Capt. Dundas: but as we are not well informed concerning the exact difference of meridians between them, and they being at least 1° 22′ distant, nothing in these observations will apply to Point de Galle.

There is certainly too much discordance between the three longitudes of Point de Galle given above; the mean of which is 80° 8' 30". As Anjenga and Cape Comorin were placed g' farther to the eastward than Capt. Huddart's observation warranted, in order to accommodate the differences between the two calculations, Point de Galle should be reckoned in 80° 11' 30". Mr. Dalrymple's time-keeper gave the difference of longitude between Anjenga and Point de Galle 3° 29' 30", which added to 76° 40' (see page 19) gives 80° 9' 30".

If we consider the respective positions of Point Pedro and Point de Galle by the different geographers, we shall have the following result:

• Deduced from Bombay, which is reckoned in 72° 40'.

+ Capt. West reckoned from Sadras, which I place in 80° 24'. He reckoned it 80o 19'; and of course, Point de Galle in 80° 22′.

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And the longitude of Point Pedro being taken at 80° 27′, Point de Galle by this rule, will be in 80° 18'.

On an occasion like this, where we are not likely to come exactly at the truth, since no one can pretend to say whether the longitude of Point de Galle be 80° 1' 30", or 80° 18"; I thought it better to insure a certain good, at the hazard of a small mistake, than to sacrifice that advantage, by adhering to a result which in itself was problematical. In other words, I judged it better to preserve the general form of the island, and consequently the respective positions of the north and south points of it, as given by D'Apres; and which appear to me to agree best with the result of the observations of longitude, taken on different sides of it; than to change those relative positions, which must have been done, had Capt. Huddart's observation at Point de Galle been adopted. I have therefore placed Point de Galle 10' west of Point Pedro (according to D'Apres); that is, in lon. 80° 17'. Had I adhered to the observations in respect of Cape Comcrin, it would have been 80° 11' 30". The mean of all the observations and deductions, is about 80° 14′ 30′′. The observations differ among themselves 14′ 30". The latitude of this Point is 6 degrees; and of Dundrahead, the southmost point of the whole island, 5° 51'.

The observations at Dundrahead, were, by Mr. Topping, 80° 39', and by Capt. Huddart 80° 23'. The Great Bassas, by Mr. Topping 81° 41'; by Capt. Dundas 81° 30'. The variation in these longitudes, shew that a series of them by the same person, and the same time-keeper, is by much the most desirable.

The longitudes on the east side of Ceylon, by 3 different gentlemen; (viz.) Capt. Cumming, Capt. West, and Mr. Topping, do not disagree so much as those on the south side of the island. They are these:

By construction. 81° 58′

82

81 55 82 82 1 82 1

82 2

In lat. 7° 40′ Mr. Topping's longitude was 82° 2′
6 33 Capt. West's

6 53 Capt. Cumming's
7 31 Ditto

Together with M. D'Apres' dimensions of the island (in the southern parts particularly), I have adopted his detail of the coast from Columbo to Vendelos Bay. From Vendelos Bay to Point Pedro, the coast in Van Keulen appears to be too nearly meridional, and his latitudes too much southwardly. Again, on the west side, from Columbo to Manar, I followed D'Apres' bearing, which is more north-eastwardly than Van Keulen's. Indeed it could not be otherwise, than that both the east and west coasts must have a greater degree of obliquity from the meridian, than Van Keulen represents: because he allows too little breadth to the south part of the island. In short, the general form of the island is D'Apres': but the particulars are collated with Van Keulen's and D'Anville's

maps.

The distance from Mentole Point, on Ceylon, to Point Ramen on the continent, I take to be less, by 11 G. miles, than Major Stevens supposed it to be, in his chart; nor can it be otherwise, to reconcile it to my position of Cow Island.

The Maldive and Laccadive Islands are copied from M. D'Apres; save that the position of the northmost Maldive Island (called by the French the head of the Islands) is placed according to Mr. Topping's observations of latitude and longitude in 1785. He made the latitude of it 7°5′, and the lon. 73° 4′; and when opposite to it on the north, he counted 32 islands; the furthest bearing SE by E.

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