Mr. COOLEY, in his learned work on Claudius Ptolemy and the Nile, Lond. 1854, has successfully shown that whilst forced to accept those popular statements which he had no authentic data to check, Ptolemy conscientiously availed himself of the best materials at his command, and endeavoured to fix his distances by means of the reports of the Greek seamen who frequented the coasts which he described, constructing his maps by means of their itineraries and the journals of trading voyages.  But a fundamental error pervades all his calculations, inasmuch as he assumed that there were but 500 stadia (about fifty geographical miles) instead of sixty miles to a degree of a great circle of the earth; thus curtailing the globe of one sixth of its circumference.  Once apprised of this mistake, and reckoning Ptolemy’s longitudes and latitudes from Alexandria, and reducing them to degrees of 600 stadia, his positions may be laid down on a more correct graduation; otherwise “his Taprobane, magnified far beyond its true dimensions, appears to extend two degrees below the equator, and to the seventy-first meridian east of Alexandria (nearly twenty degrees too far east), whereas the prescribed reduction brings it westward and northward till it covers the modern Ceylon, the western coasts of both coinciding at the very part near Colombo likely to have been visited by shipping.”—­Pp. 47, 53, See also SCHOELL, Hist, de la Lit.  Grecque, l. v. c. lxx.

[Illustration]]

[Footnote 2:  It is observable that Ptolemy in his list distinguishes those indentations in the coast which he described as bays, [Greek:  kolpos], from the estuaries, to which he gives the epithet of “lakes,” [Greek:  limen].  Of the former he particularises two, the position of which would nearly correspond with the Bay of Trincomalie and the harbour of Colombo.  Of the latter he enumerates five, and from their position they seem to represent the peculiar estuaries formed by the conjoint influence of the rivers and the current, and known by the Arabs by the term of “gobbs.”  A description of them will be found at Vol.  I. Part I. ch. i. p. 43.]

[Footnote 3:  May it not have an Egyptian origin “Siela-Keh,” the land of Siela?]

[Footnote 4:  The description of Taprobane given by Ptolemy proves that the island had been thoroughly circumnavigated and examined by the mariners who were his informants.  Not having penetrated the interior to any extent, their reports relative to it are confined to the names of the principal tribes inhabiting the several divisions and provinces, and the position of the metropolis and seat of government.  But respecting the coast, their notes were evidently minute and generally accurate, and from them Ptolemy was enabled to enumerate in succession the bays, rivers, and harbours, together with the headlands and cities on the seaborde in consecutive order; beginning at the northern extremity, proceeding southward down