Mr. Jackson, indeed, in his Travels (p. 310), states it to be a fact universally known among the rich African traders, that the Niger and the Nile are one and the same river, by means of which there is a practicable communication between Tombuctoo and Grand Cairo. Between these two cities caravans are continually passing, and a large trade is carried on; but Mr. Jackson observes, that the expense of land-carriage by means of camels is more moderate than that by water, and that the journey also is more agreeable! He gives an account of the voyage to Cairo down the Niger, having actually been performed in the year 1780 by a party of seventeen negroes, the particulars of which expedition, he says that he received from 'a very intelligent man who has an establishment at Tombuctoo.' These negroes proceeded down the Niger from Jinnie, on a commercial speculation, and reached Cairo after a voyage of fourteen months. They returned by the caravan, and arrived at Jinnie, after an absence of more than three years. Some of the facts which they reported are not a little extraordinary:--_viz_. that in several places they found the Nile so shallow, in consequence of channels cut for irrigating the lands, that they could not proceed in their boat, and were obliged to transport it some distance over-land; that they saw between Tombuctoo and Cairo _twelve hundred_ cities and towns, adorned with mosques and towers, &c. It is needless to comment upon such _hearsay_ statements, received from an African traveller or merchant more than twenty years after the transaction is said to have happened; nor would any allusion have been made to them in this place, if Mr. Jackson's book had not been much commended by distinguished critics, and quoted as an authority respecting the interior of Africa by several geographical writers. [Footnote: Edinburgh Review, vol. xiv. p. 306.] The principal, and apparently decisive, objection against this supposed junction of the Niger and the Nile, is grounded upon a comparison of the great _difference of level_ between the beds of the two rivers. From the authentic information we possess by means of Mr. Browne, respecting the countries west of the Nile, it is now clear, that if this junction takes place at all, it must be in the upper part of the Nile, before that river has quitted the higher regions of Africa, from whence it has still 1000 geographical miles to run before it reaches the sea, passing in its way through several cataracts. But it is utterly incredible that the Niger, which, in order to reach this part of the Nile, must have run at the least 2300 miles, should not in so long a course have descended to a level considerably lower than that which is here described. This objection is urged with great force by Major Rennell, who justly considers it as being entirely decisive of the question; but he has added several other arguments, which those who take an interest in this question, will do well to consult.