What we do know, with any degree of certainty about this transit, is briefly as follows:—The navigation of the Red Sea in the vicinity of Suez is rather intricate, abounding in shoals, but there is secure anchorage, and sufficient draft of water for merchant ships of considerable burden. The Mediterranean off the eastern extremity of Lake Menzaleh is rather shallow, tolerably sheltered from the west wind, which prevails for a part of the year, but exposed to the north wind. Between Suez and the site of the ruins of Pelusium at the eastern end of the lake, the land is low and level, apparently for a part of the way between the level of both seas. The low land receives in the wet season the drainings of the high land on the east, which is a northern continuation of the mountains between the gulfs of Suez and Akaba. In addition to this, the land to the westward (northward of the Mokattam mountains which terminate near Cairo) has a twofold slope,—the principal northward to the Mediterranean, the secondary eastward to the line of country we are now describing. Originally, there appears to have been a branch of the Nile entering the Mediterranean near where the ruins of Pelusium now are, and those intermediate branches between that and the Damietta branch. The first mentioned is now closed, the other two very much obstructed; but their waters still find a way to the coast, though diminished by artificial works, and appear to be the cause of the collection of shallow water called Lake Menzaleh. Here, then, we have sixty geographical miles of a low country, with no considerable undulations, towards which the waters of Arabia Petræa flow in their season, and towards which a considerable portion of the waters of the Nile would flow if left to fall on the natural declivity of the country. There is an abundant supply of water for a ship canal. The surface of the ground is in some places covered with drift sand, but not uniformly nor even for the most part. The subsoil is hard, clayey or pebbley. The bent-grasses might be cultivated, as they have been in Holland, to give firmness to the drift sand where it occurs; and this superficial obstacle removed, the subsoil is favourable to the construction of a permanent water-channel. The great difficulty would be the construction of works by which access to the canal is to be obtained from the Mediterranean. Apparently they would require to be carried far out into the sea; and apparently it would be difficult to prevent their being sanded up by the waves which the north winds drive upon the coast for a great part of the year.