Diversity of Advantage both natural and acquired is the sole ground of Trade both domestic and foreign; and consequently by means of trade the peculiar advantages of each are fully shared in by all. It is perhaps less obvious but surely equally true, that the greater the relative diversity of advantage as between two exchangers, the more profitable does the exchange become to each. If the Vale of Sharon had been twice as fertile as it was, and the cedars of Lebanon twice as large and lofty as they were, the easier and better would Israel have gotten its timber, and the more secure and abundant would have become the food of Tyre and Sidon; and, therefore, the more unreasonable, or rather the more absurd and wicked, would have been any envy or jealousy of either of the superior advantages at any point or points of the other. So universally. By the divine Purpose as expressed in the constitution of Nature, in the structure of Man, and in the laws of Society, Trade in good measure and degree imparts to each the bounties of all, arms each with the power of all, and impels each by the progress of all. One other important matter is closely connected with these two Renderings, which is the fifth bit in succession of our present analysis, namely this, that traffic renderings always make necessary new and better routes of travel and transportation. It is mainly for this reason, that persons and things have to be carried to distances less or greater in order to consummate these Renderings of home and foreign commerce, that roads by land and routes by sea have been sought for and found, made and made shorter, improved as to method and facilitated as to force, from the dawn of History until the present hour. It was to get the goods of India, and so find a market for the goods of Europe, that the earliest land routes between the two were tried and maintained. The ground-thought of Columbus, meditated on for years, was to discover a new commercial way to India; Magellan with the same intent sailed westward through the Straits that wear his name, and so circumnavigated the globe; repeated searches mainly with the mercantile view, never long intermitted, have attempted ever since the North-West or the North-East passage to India; Vasco da Gama in 1497 boldly accomplished the East passage, and thus changed for all the Continents the channels of trade; the West now trades with all the East through the Suez Canal, dug for that express purpose; and the words, "Panama" and "Nicaragua" are upon everybody's lips, simply because through Central America is the shortest and safest route for men and goods to and from all the Oceans.