Mr. AMES was sensible that any further discussion of the present subject was unpleasant, nay, it was painful to the committee; but he had such impressions on his mind with regard to its importance, that he must trespass on them again. On all subjects demonstration is desirable, but there is only one science capable of complete demonstration. Many other sciences admit of different degrees of demonstration; but of all the sciences on earth, the science of politics is the least capable of affording satisfactory conclusions, while it is the one that, from its importance, requires the greatest degree of certainty; because when we are to consider those things which relate to the welfare of nations, it is of consequence, and nothing can be more desirable than that we adopt just principles in order to come at proper conclusions. In this science it is dangerous to adopt the visionary projects of speculators instead of principle. We ought to be cautious, therefore, in selecting the information upon which we form our system. He trusted to make it appear in the course of his arguments, that the propriety of the particular measure under discussion depended upon local knowledge, and yet it would be found of national concern. He believed it could be clearly proved to be as much the interest of one part as of another to have the duty reduced. It was laid down as a principle that all duties ought to be equal. He believed, if gentlemen gave themselves time for consideration, they would not contend this duty was equal. He said he had made some calculations, which demonstrated the inequality to a very surprising degree. The tax operated in two ways: first, as a tax on a raw material, which increased the price of stock and narrowed the sale; and second, as a tax on an article of consumption. It required the distillation and the consumption to be equal in every part of the Union to render the duty equal in its operation; but no gentleman contended that the consumption or distillation was equal. The gentleman from Virginia said, on a former occasion, that Massachusetts would not contribute her proportion of the national revenue, because her exports were not equal to the Southern States, and of consequence her imports are less; but if this fact is examined, it will be found that she does export in full proportion with the Southern States. Examine her custom-house books, and you will find it; but Massachusetts is greatly concerned in navigation, and the wages of her seamen ought to be added to the amount of the profits of her industry. Then if we consider her consumption, we shall find it in proportion also. Admitting the people of New England to live more moderate than the opulent citizens of Virginia or Carolina, yet they have not such a number of blacks among them, whose living is wretched; consequently, the average consumption per head will be nearly the same. The fact is, that all taxes of this nature will fall generally in proportion to the ability to pay.