A French ironmaster exclaims: Preserve us from the invasion of English iron. An English landowner exclaims in return: Preserve us from the invasion of French corn. And then they proceed to interpose barriers between the two countries. These barriers create isolation, isolation gives rise to hatred, hatred to war, war to invasion. What does it signify? cry the two sophists; is it not better to expose ourselves to an eventual invasion than accept an invasion which is certain? And the people believe them, and the barriers are kept up. And yet what analogy is there between an exchange and an invasion? What possible similarity can be imagined between a ship of war which comes to vomit fire and devastation on our towns, and a merchant ship which comes to offer a free voluntary exchange of commodities for commodities? The same thing holds of the use made of the word _inundation_. This word is ordinarily used in a bad sense, for we often see our fields injured, and our harvests carried away by floods. If, however, they leave on our soil something of greater value than what they carry away, like the inundations of the Nile, we should be thankful for them, as the Egyptians are. Before we declaim, then, against the inundations of foreign products--before proceeding to restrain them by irksome and costly obstacles--we should inquire to what class they belong, and whether they ravage or fertilize. What should we think of Mehemet Ali, if, instead of raising, at great cost, bars across the Nile, to extend wider its inundations, he were to spend his money in digging a deeper channel to prevent Egypt being soiled by the foreign slime which descends upon her from the Mountains of the Moon? We display exactly the same degree of wisdom and sense, when we desire, at the cost of millions, to defend our country.... From what? From the benefits which nature has bestowed on other climates. Among the metaphors which conceal a pernicious theory, there is no one more in use than that presented by the words _tribute and tributary_. These words have now become so common that they are used as synonymous with _purchase and purchaser_, and are employed indiscriminately. And yet a tribute is as different from a purchase as a theft is from an exchange; and I should like quite as well to hear it said, Cartouche has broken into my strong-box and purchased a thousand pounds, as to hear one of our deputies repeat, We have paid Germany tribute for a thousand horses which she has sold us. For what distinguishes the act of Cartouche from a purchase is, that he has not put into my strong-box, and with my consent, a value equivalent to what he has taken out of it. And what distinguishes our remittance of £20,000 which we have made to Germany from a tribute paid to her is this, that she has not received the money gratuitously, but has given us in exchange a thousand horses, which we have judged to be worth the £20,000.