The recent reports by Leo Frobenius on his findings further up into the interior, aside from giving us a picture of present-day conditions of cities which he believes to date back to pre-classical and pre-Christian times, also show the absence or scarcity of durable producing materials. But, most important of all, the report indicates the grandeur of African cities in ancient times. In discussing the buildings in the present-day city of Ilife, which he believes was the capital or center of an ancient African theocracy, he says: "There can be no doubt that the entire plan and style of architecture gives the city of Ilife a pleasantly dignified character. If, however, I am to summarize all the life and activities of this city of palms and divinities, I cannot, indeed, speak of anything great and sublime, because that lies buried too deep beneath the soil and debris of centuries, yet I can say that it has a dreamy respectability." But speaking specifically upon the building which now serves as the palace of the great religious headman of Yorubaland, he says: "The edifice rests upon foundations not of sun dried, but of fine burnt brick." Taken as a whole, the present-day structure conveys "the impression of grandeur in decay." "Such," he says, "is a sketch of the city whose effect is heightened by the noble ruins of the palace of this Holiness and the consciousness of its traditional past."[15] We may now turn for a brief consideration of those strange and most interesting structures of the Sudan, the tombs of their ancient dead. All through the Sudan, and especially in Nigeria, are to be found great conical dome-shaped structures of baked clay ranging in size from sixteen feet in height and sixty-six feet in basal diameter to seventy feet in height and two hundred and twenty feet in basal diameter.[15a] These structures were first mentioned by Lieutenant Louis Desplaynes in his report of _Une Mission archeologique au Sudan francais_,[16] but the first close study of these tombs was made by Frobenius in 1911. Frobenius tells us that these tombs are of three main types: first, a small size; second, an intermediate size; and third, a large size. This last type, he tells us, was an extraordinary large construction, averaging about seventy feet in height and six hundred and fifty to seven hundred feet in basal circumference. The external structure is connected with an underground structure composed of a number of subterranean chambers and compartments, extending in every direction of the compass, sufficient to accommodate the remains of a great number of notables and royal personages.