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The SE A COASTS and ISLAND S.
ALCUTTA' is the point
' I shall set out from, as well from its being determined by several observations of longitude and latitude,''a's from its having a measured line of considerable extent stretching from it both to the east and west.
I shall first pursue the route westward to the mouth of the Indus; and then return to Balasore, and go eastward to the entrance of the strait of Malacca. .
Calcutta, the capital of the British possessions in India, as being the residence of the General Council, has its citadel placed in latitude 22° 33' north ; and in longitude, by a medium of the observations of four different gentlemen, 88° 28' east from Greenwich *.
Balasore, situated about 101 geographical miles of from Calcutta, is the extreme point of the Bengal survey on the SW; or on the quarter towards Madras. Col. Pearse's return from the Carnatic, after the termination of the late war, afforded an opportunity of carrying a measured line from Madras to Balasore, which had long been a desideratum ; as the exact positions of the intermediate stations of Masulipatam, Visagapatam, Ganjam, and Cattack, points on which
many others eventually depended, were wanted : and although there might be no great reason to suppose that Masulipatam and Visagapatam were much out of place, in the former map, yet Ganjam and Cattack were doubtful. Col. Pearse's industry and attention have amply supplied what was wanting, within this line. He directed the whole to be measured with a perambulator, and corrected each day's work, or at least, every considerable interval, by observations of the latitude ; and the general course being little more than 3 points from the meridian, the differences of latitude, were applicable to the correction of the distance thro' each particular interval : and for a check on the whole, we had already in our possession, observations of longitude repeatedly taken at Calcutta and Madras. The whole extent of Col. Pearse's measured line, in road distance, was near goo British miles; a work of no small labour.
* All the latitudes mentioned in this work, being north of the Equator, and all the longitudes east of the meridian of Greenwich, I shall in future mention only the terms latitude and longitude, leaving the species of each, to be understood,
+ I have made use of Geographic miles, or those of 60 to a degree, in the account of the construction of the map ; and of British statute miles in giving the comparative extent of countries. They are distinguished by G. miles, and B. miles.
The longitude of Fort William, the citadel of Calcutta, as abovesaid, taken at 88° 27' 45"*, from the medium of 4 observers ; and that of Madras 80° 24' 40" f, from the medium of 3 observers, gives a difference of meridians of 8 degrees, 3 minutes. It remains then, to compare with this, the difference of longitude found by Col. Pearse's measured route, as communicated by Mr. Pringle in the
map drawn by him, and sent to the East India House. Balasore, by the survey, is 1° 26' 30" west of Fort William, and must therefore be in 87° 1' 30". Col. Pearse reckons it i' 15" more westerly; but I adhere to the survey. From Balasore to Ganjam, in lat. 19° 22', Col. Pearse reckons 95 miles of westing, or 1° 41' 26" difference of longitude ; which brings Ganjam in lon. 85° 20' 4" I. And from Ganjam to Madras he made 5° 2' 18" west: whence the
* Hon. Thomas Howe
Medium 88° 27' 45"
88 26 To which may be added the French observation at Ghyretty, which place is reaft from Calcutta + Mr. Howe
Medium 80° 24' 40"
longitude of Madras, would be 89° 37-44" Here is found an excess of about 7 minutes difference of longitude, more than the observations give. But in examining the map abovementioned, it appears that the difference of latitude between Ganjam and Madras by account, exceeded that by observation 8' 30"; and if this is to be imputed to excess of distance (which is highly probable) an ex.cess of longitude must also have taken place; and this error will amount to about 6'48”; or nearly the difference in question. This trifling error of 7 minutes in a difference of meridians of 6 degrees and a half, to whatever it may be owing; whether to overmeasurement by the wheel ; variation of the compass; defects in the instruments ; or errors in the observations of longitude ; or partly to all these causes; is very immaterial, to general geography. i The result Mhews, that we may consider the difference of meridians between the two places, as determined near enough for the purposes of navigation, or general Geography.
I must not omit to mention that Capt. John Ritchie, by direction of the Bengal Government, in 1770 and 1771, took the bearings and distances in a general way, from Madras to Balasore ; and his result came within one minute of the longitude by observation. : But some of his intervals were not well proportioned. His position
of Masulipatam, indeed came out only 1' to the east of Col. Pearse’s ; but Visagapatam was 7', and Ganjam 22' more westerly.
Although Col. Pearse's route serves to fix most of the principal places, on or near the coast, yet oftentimes it deviated considerably, vand for a tength of space, from the coast; as between Balasore and Jagarnaut; and between Visagapatam and Ongole. These blanks are supplied from the materials of Capt. Ritchie, Major Stevens, Major Polier, Mr. Cotsford, and others.
First, from Balasore, to Point Palmiras. This was done by Capt. Ritchie, by a series of triangles, formed by three surveying vessels; and corrected by obfervations of latitude. The result, placed Point Palmiras, directly fouth of Balasore : that is, in lon.
87° 1' 30"; lat. 20° 44'. From Point Palmiras to Jagarnaut Pagoda, the coast was traced in a more cursory manner ; and accordingly, the bearing and distance between Balasore and Jagarnaut is very differently given by Col. Pearse and Capt. Ritchie : the account of the former being only 54' 30" difference of longitude ; and that of the latter, 1° 16'. This very considerable difference is too striking, not to be particularly noticed ; and requires that some observations should be made with time-keepers, to ascertain the relative positions of Jagarnaut, Point Palmiras, and Balasore. Wherever the mistake may lie, it is of great importance to have it rectified: for if Col. Pearse's bearing be true (and there appears no reason to doubt it) there must be a very considerable error in the course between Jagarnaut, and Balasore road, in Capt. Ritchie's chart.
The longitude of Cattack is scarcely altered from what it was in the former map of India ; where it was placed on the authority of Capt. Campbell, in lon. 86'. It is now in 86° 1' 30"; and its latitude stands as before.
From Jagarnaut to Ganjam, the particulars of the coast, are from Col. Pearse's map, collated with those of Ritchie’s and Campbell's. From Ganjam to Poondy, is taken from the map of the Itchapour district ; and Col. Pearse's route on it, which may be traced from Ganjam to Bindi (near Poondy) furnishes the means of correcting the compass of that map, which was faulty in a very considerable degree. Bindi serves as a connecting point for the two maps ; as Nauparah or Nowparah, a little farther to the Sw. does for Pearse's, and Cridland's map of the Tickley district. The coast between Poondy and Bimlepatam is sketched from Lieut. Cridland's
from Major Polier's journal, and other MSS. From Bimlepatam to Visagapatam is from Col. Pearse ; and from thence to Coringa from a MS. map, compiled during Col. Forde’s expedition to Masulipatam, in 1759; collated with Capt. Ritchie's map:
As there have been some observations taken at Visagapatam to ascertain the longitude, it is proper to take notice of them, and to compare the result with the longitude deduced from Calcutta and Ganjam, by Col. Pearse's line. This gives 107,1 miles of westing, or 1° 52' 54" difference of longitude, from Ganjam to Visagapatam; from which if we deduct the proportion of the error in the diftance (see page 10) the true difference of longitude will be r° 50' 39" ; which taken from 85° 26' 4", the longitude of Ganjam, leaves 83° 29' 25" for that of Visagapatam. But Col. Pearse's observation was 84° 23' 30' and Mr. Ruffel's 83° 21' 30". Its latitude is 17° 42'.
From Coringa to Masulipatam, the figure of the coast is from Major Stevens, as Col. Pearse's route goes far inland, by way of Rajamundry, Ellore, &c. and does not again approach the coast near enough to determine its position, till it comes to Vantipollam, near Ongole. These maps of Major Stevens's and of Col. Pearse's join at the points of Siccacollum, on the bank of the Kistnah ; at Rajamundry, and at Samulcota. These 2 maps differ confiderably in the extent between Siccacollum and Samulcota; Major Steven's giving 61 miles less than the other (error of distance allowed) but, I believe, Major Stevens's distance was measured, only between Siccacollum and Narsapour.
- Mafulipatam has its position very satisfactorily determined, by Major Stevens's measurement from Siccacollum, a place in Col.
It is 17,4 G. miles east; and 3,3 south of it; and comes out 48' of longitude, east of Madras, or corrected (see again. page 10) 47'; its longitude being 81° 12'; lat. 16° 8' 30".
From Masulipatam to. Madras, the figure of the coast, is generally from Capt. Ritchie, corrected in certain points by the land survey, of Col. Pearse. For as the latter came close to the coast at Vantipollam, Carwaree, and Ramecapatam, it appeared that: Capt. Ritchie's chart required correction in the great bay between the latter place and Point Divy. I found it necessary also to reduce