Early in 1819, struck with the prevailing condition of the United States, he commenced writing on political economy, investigating the causes, and pointing out the necessity for protecting our industries against foreign competition. Few men ever enlisted in any public cause with more enthusiasm, few ever worked with more energy and industry in such a cause. He was one of the founders of the Philadelphia Society for the Promotion of National Industry; he attended conventions in various parts of the country, and he made more extensive contributions to the literature of the subject than any other man had then done on this continent. Some idea may be formed of the extent of this work when it is stated that between 1819 and 1833 his books and pamphlets on this question reached an aggregate of 2,322 pages. To no other man, not in public life, was the first protective tariff of 1824, as well as that more protective one of 1828, due. These were results which would have exerted a permanent influence on the country but for the nullification movement of South Carolina and Georgia. This latter movement produced Clay’s Compromise Tariff Act of 1833, which was only abandoned in 1842 in the midst of a bankruptcy so widespread and universal that it involved not merely individuals and banks and other corporations, but state governments, and even the government of the United States itself. Mr. Carey was much discouraged by the illiberal conduct of manufacturers and others who had much at stake in the cause, and he ever after believed that to this illiberality and supineness was due the triumph of nullification, for it did triumph in the enactment of the Compromise Tariff, Act of 1833. However, amid these discouragements, he derived some consolation from a recognition of his services by a portion of his fellow countrymen. In 1821 he was presented by citizens of Wilmington, Del., with a handsome piece of silver plate bearing the following inscription: “A tribute of gratitude to Mathew Carey, Esq., in approbation of his writings on political economy; presented by some friends of National Industry, in Wilmington, Del., and its vicinity, April, 1821.” In 1834 he was presented with a service of plate by citizens of Philadelphia and others, “as a testimonial of their respect for his public conduct and their esteem for his private virtues”; who deemed his “whole career in life an encouraging example, by the imitation of which, without the aid of official station or political power, every private citizen may become a public benefactor.” Sometime previously he received two silver pitchers from other citizens of Philadelphia. In 1824 he was instrumental in reviving and carrying through the project for the construction of the Chesapeake and Delaware Canal, which had lain dormant from 1805. This undertaking involved weeks of labor, and of personal solicitations for subscriptions.