That Agatharcides had access to and made ample use of the journal of Nearchus (of which we have given such a complete abstract), is evident from various parts of his work; but it is also evident, by comparing his description of those countries and their inhabitants, which had been visited and described by Nearchus, that he had access to other sources of intelligence, by means of which he added to the materials supplied by the latter.

It will be recollected that Nearchus describes in a particular manner, the Icthyophagi of Gadrosia:  Agatharcides also describes Icthyophagi, though it is not clear whether he means to confine his description to those of Gadrosia, or to extend it to others on the coast of Arabia and Africa.  The mode practised by the Icthyophagi, according to him, is exactly that which was practised by them in catching fish, according to Nearchus:  he also coincides with that author in various other particulars respecting the use of the bones of whales, or other large fish, in the construction of their houses; their ignorance and barbarism, their dress and mode of life.  All this he probably borrowed from Nearchus; but he adds one circumstance which indubitably proves, that the knowledge of the eastern part of the world had considerably advanced since the era of Alexander:  he expressly states, that beyond the straits that separate Arabia from the opposite coast, there are an immense number of islands, scattered, very small, and scarcely raised above the surface of the ocean.  If we may advert to the situation assigned to these islands, on the supposition that the straits which separate Arabia from the opposite coast, mean the entrance to the Gulph of Persia, we shall not be able to ascertain what these islands are; but if in addition to the circumstances of their being scattered, very small, and very low, we add what Agatharcides also notices, that the natives have no other means of supporting life but by the turtles which are found near them in immense numbers, and of a very large size, we shall be disposed, with Dr. Vincent, to consider these as the Maldive Islands.  It may be objected to this supposition, that the Maldives are situated at a very great distance from the straits that separate Arabia from the opposite coast; but a cursory acquaintance with the geographical descriptions of the ancients will convince us, that their information respecting the situation of countries was frequently vague and erroneous, (as indeed it must have been, considering the imperfect means they possessed of measuring or even judging of distances, especially by sea) while, at the same time, their information respecting the nature of the country, the productions of its soil, and the manners, &c. of its inhabitants, was surprisingly full and accurate.  In identifying places mentioned by the ancients, we should therefore be guided more by the descriptions they give, than by the locality they assign to them.  Agatharcides, it is true, adds that these islands extend along the sea, which washes Gadrosia and India; but he probably had very confused notions of the extent and form of India; and, at any rate, giving the widest latitude to the term, the same sea may be said to wash Gadrosia and the Maldive Islands.  If these are the islands actually meant by Agatharcides, it is the earliest notice of them extant.