3rd. That the mean fall from the level of the Red Sea to that of the Mediterranean (say thirty feet) is sufficient to keep the artificial channel clean, if the fall be properly economised; and also that it would be able to preserve its mouth in the Bay of Pelusium in a navigable state at all seasons. 4th. That a navigation of still water with locks could not be long maintained with advantage, under all the circumstances of the case. 5th. That a broad and deep stream like that of the Dardanelles could not be produced by natural operations, assisted slightly by art; but that the attempt would be pregnant with mischief in some quarters, and result in disappointment. 6th. That a direct and perfectly controllable channel, of a uniform size and shape and incline, would be the safest and most appropriate undertaking of which the circumstances permit, and under the imperfect information we possess. It must, however, be confessed, that no definitive opinion can be given, or very satisfactory estimates assumed, until a new and detailed survey, having the express objects in view, is completed, comprehending the necessary levellings and borings and maritime surveys of the ports at the termini of the Canal. With respect to the land survey, were all the necessary persons and means duly prepared to commence operations in the beginning of October, it is probable the investigation might be completed in the beginning of the following May, and a true solution given to this great geographical, commercial, and engineering question. As mankind multiply and make progress in arts and civilization, new wants arise, and the ingenuity and industry of man is taxed to discover new sources of wealth, maintenance, and occupation: and we find, under the dispensations of an all-wise Providence, that at suitable seasons resources are unveiled which have been long provided but concealed until the fit occasion presents itself. Amongst the numerous administrations of the same wise and merciful design, it is not unreasonable to believe that the completion of navigable channels across the Isthmuses of Suez and Darien are enterprises amongst the events designed to minister to the growing wants and improvement of the human race. * * * * * In the preceding pages an endeavour has been made to show the superiority of a direct communication between the two Seas (which would provide for the speedy passage of large ships at all seasons), over a communication partly through the medium of the Nile, which would be interrupted in the dry season, and prove tedious at all times; and it now remains to say a few words on the comparative value of railways.