certainly the geographical information obtained on these countries by Herodotus and Edrisi was more accurate than the speculations of many modern geographers. Observation had demonstrated to the moderns that no large river emptied itself into the ocean on the north-west coast, though it required a more accurate acquaintance with the Senegal and the Gambia before it was fully ascertained that they were not the outlets of this great stream. The progress of navigation along the south-eastern shores of Africa also showed that no large river emptied itself into the sea along that coast; while the settlements of the Portuguese on the coast to the south of Cape Lopez, led them, at an early period, to adopt the opinion afterwards supported by Mungo Park and Mr. Barrow, that one or more of the rivers in their vicinity were the outlets of the great river of the interior of Africa. Two celebrated geographers, D'Anville and Major Rennell, however, espoused the theory of the waters emptying themselves into the Wangara, or great marsh; which argument underwent various modifications in the hands of different geographers; and though the probability of its emptying itself into the Gulf of Guinea had been pointed out on the continent, and vigorously supported in this country, an expedition was fitted out to explore the Congo or Zaire, which, though unfortunate to the individuals concerned, was yet satisfactory in a geographical point of view, and demonstrated that the rivers south of Cape Lopez were not the outlets of the waters of the Niger, and gave origin to a speculation which partook of all the characters of a romance of the desert, beneath the sands of which its author buried the gigantic stream, loaded with the waters of the Wangara or Lake Tchad, to make it flow into the Mediterranean at the Syrtis of the ancients. In the history of geography there are no examples of greater perseverance and courageous determination than in the efforts made to triumph over the difficulties presented in the solution of this important question. Since 1815, there has scarcely a year passed in which a new attempt has not been made; and of these, if we recede a little farther back, twenty-five were made by our countrymen, fourteen by Frenchmen, two by Americans, and one by a German; of which but a small number, since the days of Houghton, have not fallen victims to their heroic devotion.