Although it was not intended for voyaging, the ark must necessarily have been a perfect model of a vessel, meant to float upon the waters. To some extent, too, it must have been fitted to ride upon turbulent billows; for it "went upon the face of the waters" for upwards of seven months, and before it rested finally on the top of Mount Ararat, "God made a wind to pass over the earth, and the waters assuaged." In regard to its size, the most interesting way to consider it, perhaps, will be to compare it with the _Great Eastern_, the largest ship that has yet been built by man. Assuming a cubit to be about 18 inches, the length of the ark was about 450 feet, its breadth about 75 feet, and its depth about 45 feet. The _Great Eastern's_ length is 680 feet, its breadth 83 feet, and its depth from deck to keel 60 feet. The ark was built of gopher-wood, which is thought by some to be pine, by others cedar. It consisted of three stories, and had a window and a door, and was pitched within and without. But it had neither masts nor rudder; and it is evident that, although it was man's refuge, the ark was not designed to be managed by man, for after Noah and his family had entered in, God took on himself the guidance and preservation of their vessel. Thus our Saviour--of whom the ark was a type--specially guides and protects those who flee to him for refuge. But although we have noticed the ark as being the first ship, we cannot with propriety place it in the front of the history of navigation. After the flood the ark seems to have been soon forgotten, or at least imperfectly remembered, and men reverted to their little canoes and clumsy boats, which sufficed for all their limited wants. It was not until about a thousand years later in the world's history that men built ships of considerable size, and ventured on prolonged _coasting_- voyages, for the purposes of discovery and commerce. Navigation had been practised, and the art of ship-building had made very considerable progress, long before men dared to lose sight of the shore and venture out upon the mysterious bosom of the great unknown sea.