There is a personal history belonging to the development of canal navigation of a much more engrossing interest than can usually be claimed for so unromantic a type of institutions. The annals of that history extend over many centuries. They reach back even to the times of ancient Egypt, the cradle of the sciences, and were contemporaneous with the building of the Pyramids. Menes, who lived 2320 years before the Christian era, constructed water-courses, which were simply canals, for carrying off the superfluous waters that reduced the greater part of Egypt in his time to the condition of an extensive marsh.[19] Sesostris, 1659 B.C., undertook the cutting and embanking of canals on a more extensive scale, carrying them at right angles with the Nile, as far as from Memphis to the sea, for the quick conveyance of corn and merchandise.[20] Ptolemy II. (Philadelphus) completed a canal, which had been commenced and continued by several previous sovereigns, and which is said[21] to have afforded a connection with the sea;[22] while even at this early date, gates or sluices were constructed, which opened to afford a passage through the Egyptian canal to the sea.[23] In Roman times, again, Julius Cæsar, Caligula, and Nero were canal-makers, having each in his day attempted to unite the Ionian Sea with the Archipelago, through the isthmus of Corinth—an undertaking which is only in our own day being consummated. The emperor Trajan was also greatly interested in canals, as his correspondence with Pliny proves, while all the principal Roman consuls and generals appear to have possessed some knowledge of hydraulics, and applied that knowledge to useful purpose. Charlemagne attempted to unite the Rhine with the Danube, and to establish water communication between the German Ocean and the Black Sea. Leonardo da Vinci was equally great as a canal-maker and a painter, having constructed some of the earliest canals in Italy. The Doges of Venice, “the City in the Sea,” naturally paid much attention to the same subject, which was, indeed, essential to their convenience, security, and prosperity. It is to the credit of many of the sovereigns of France that they have sought to promote the security and welfare of their country by similar means. Henry II. employed Adam de Crapone, about 1555, to cut the Canal of Charolais; and Henry IV. continued the work. Louis XIV. engaged an Italian to construct one of the greatest of the French canals—that of Languedoc, which is elsewhere referred to. In more recent times Napoleon Buonaparte and Napoleon III. have interested themselves actively on behalf of canal navigation; and it appears to have been by a mere chance that the latter did not become a canal administrator in Central America, where he took a keen interest in the proposed ship canal across the isthmus of Nicaragua.