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FORT ST. GEORGE: December 13th, 1844.
The following letter, pointing out an error in the position assigned in the Charts to the Laccadive Islands and the shoals in their vicinity, is published for general information.
To Captain John Pepper,
No. 199 of 1844.
Acting Superintendent of the I. Navy,
Sir,-I beg to bring to your notice that on the arrival report of the Barque Falcon on the 8th instant, "it is stated that the Vessel struck on the Byramgore shoal, of the Laccadives, when, by her reckoning, her latitude was 12°—1′ North, and longitude 71°40′ East of Greenwich, and recently, another vessel, the Ceylon, bound to this Port, was wrecked on the Cherbaniani Bank, when, by her reckoning her latitude was 12-22' North, and longitude 71°-51' East. In the first case the position of the vessel would appear to the Commander to be 23 miles to the Westward of the shoal, and in the second case 18′-20.” "My object in addressing you, is to point out, that the dangers of the Laccadive group, are all placed 18 "miles of longitude too much Easterly, on the Chart of the most recent survey, executed by Captain Moresby of the Indian Navy, in 1828, an error which is likely to prove fatal to some Ships, passing to the Westward of the group on their passage to this Port. In justice to Captain Moresby, I would state, that the error
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arises from the longitude of Mangalore Flag Staff at the time af the survey, being allowed to be 18-18" to the Eastward of the correct position, as determined by the grand trigonometrical operations with reference "to the longitude of Madras Observatory. The first station at the Laccadives, was the Cherbaniani bank, "and the distance between it, and Mangalore Flag Staff was determined by Chronometric admeasurement, after which all the other Islands and dangers were determined from the Cherbaniani bank, consequently the relative bearings, and distances of each must be correct, but the erroneous longitude East of Greenwich "affects the whole.
**
"I would beg to suggest, that notice be given to Ship Masters, (who may be navigating by that Chart) "of the necessity of deducting 18 miles of longitude, from the positions assigned to the banks and islands "of the Laccadives, to obtain their correct positions."
Master Attendant's Office, Bombay,
11th November, 1844.
I have &c.
(Signed)
DAN. ROSS, Master Attendant.
Published by order of the Most Noble the Governor in Council.
(Signed) J. F. THOMAS,
Acting Chief Secretary.
A due attention to the foregoing notice would put those Commanders on their guard who are na- vigating with Charts and sailing directions antecedent to the date thereof, but it is their bounden duty at every port of their departure to search for and obtain every nautical information of the very latest date for guidance on their intended voyage.
Such a needful enquiry would have enabled the Commanders of the Wuzeer and Hamoody to provide themselves with Captain Moresby's excellent Chart of the Laccadives, corrected and publish- ed in 1845 wherein the Shoals referred to are thus laid down.
Latitude.
Longitude.
D
1
#
G
J
Cherbaniani
>>
N. W. extreme... .12. 22. S. W.
.12. Northern extreme...11.
30 N.
15.
30
13
59.
71. 55. 30 E. 71. 56. 30 71. 51. 20
>>
"
17
Byramgore N, W
22
"
71. 45. 71. 54.
40
*1
"
"
1
..11. 55. South eastern ...11. 47.
To this Chart the following notice is appended.
"In the present Edition the Longitudes have been corrected by the Trigonometrical Survey of India- according to which Mangalore Flag Staff is 5° 25′ 22" West of Madras Observatory which is assumed to be 80° 14′ 15′′ East of Greenwich, the Longitude of Mangalore will therefore be in 74° 48′ 53′′ East.”
Chart Office, East India House 1845.
And, in the 4th Edition of Raper's excellent treatise on Navigation, the foregoing Shoals are thus laid down.
Cherbaniani-South end dry sand.... Byramgore-Wreck on south part
о
J
O
.12. 16 N. .11. 48
71. 56 E. 71. 50
"
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And in the last Edition of Horsburgh's East India Directory at page 496-7; It is notified that a Chart of the entire group of the Laccadiva from the survey of Captain Moresby, corrected to the year 1850, is published by the East India Company, and the following description is given from this Chart and the remarks of that Officer.
“Cherbaniani or Beleapani reef of Coral rocks, visible at low water, is dangerous to approach, having no "soundings half a mile off; and on the Northern and Southern extremities there are two sand banks about 8 feet above high water mark; the extent of the reef is 8 miles or from Latitude 12° 16' to 12° 24' N., its "western edge preserving nearly a straight line N. W. and S. E., and the Eastern edge forms a semi- "circle from the North and South points of 3 or 4 miles in breadth. The South point is in Longitude 71° "53′ East. The flood was found to run N.W. and the ebb S.E. 1 mile per hour on the springs; high water
at 11 hours on full and change of the moon.
*C
Byramgore or Chereapani reef is, including its bank, 12 miles long, (N. N.W. and S. S.E.) and about 5 "miles wide, having its South point in Latitude 11° 58′ N.,* Longitude 71° 50' E. The bank which is very steep, closely surrounds the reef except to the North Eastward where it projects 3 miles beyond it with soundings from 4 to 8 fathoms. The Coral rocks forming the reef are just discernible at low water "and the bottom is distinctly visible on the bank; but as there are no soundings near this or the Cher- "baniani reef the approach to them is very dangerous, as the noise of the Surf could not be heard unless a Ship was to leeward in calin weather, and the current frequently sets 12 or 15 miles during the night in uncertain directions although usually between S.E. and S.W. during the months of February, March and April."
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Commanders of Ships, when consulting the best authorities for their guidance, would do well to bear in mind at all times that the force and direction of the wind, and the heave of the Sea have more or less effect on the set and velocity of the current; and to be on the safe side (especially hen in the vicinity of Rocks and Shoals, so steep to as are the Laccadive, the Maldiva and the
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