It was this change in the South that produced the irritating discussions in Congress,--discussions always resulting in sectional bitterness and sometimes threatening the public safety. The tariff question has in fact been more frequently and more elaborately debated than any other issue since the foundation of the Federal Government. The present generation is more familiar with questions relating to slavery, to war, to reconstruction; but as these disappear by permanent adjustment the tariff returns, and is eagerly seized upon by both sides to the controversy. More than any other issue, it represents the enduring and persistent line of division between the two parties which in a generic sense have always existed in the United States;--the party of strict construction and the party of liberal construction, the party of State Rights and the party of National Supremacy, the party of stinted revenue and restricted expenditure, and the party of generous income with its wise application to public improvement; the part, in short, of Jefferson as against the party of Hamilton, the party of Jackson as against that of Clay, the party of Buchanan and Douglas as against that of Lincoln and Seward. Taxes, whether direct or indirect, always interest the mass of mankind, and the differences of the systems by which they shall be levied and collected will always present an absorbing political issue. Public attention may be temporarily engrossed by some exigent subject of controversy, but the tariff alone steadily and persistently recurs for agitation, and for what is termed settlement. Thus far in our history, settlement has only been the basis of new agitation, and each successive agitation leads again to new settlement. EXPERIENCE IN TARIFF LEGISLATION. After the experience of nearly a century on the absorbing question of the best mode of levying duties on imports, the divergence of opinion is as wide and as pronounced as when the subject first engaged the attention of the Federal Government. Theories on the side of high duties and theories on the side of low duties are maintained with just as great vigor as in 1789. In no question of a material or financial character has there been so much interest displayed as in this. On a question of sentiment and of sympathy like that of slavery, feeling is inevitable; but it has been matter of surprise that the adjustment of a scale of duties on importations of foreign merchandise should be accompanied, as it often has been, by displays of excitement often amounting to passion.