The decade of the twenties was one of great industrial activity on the part of the American people. Manufactures increased. The Erie Canal was completed, others were commenced, and there was a fever of excitement about them. The first railroads were projected, and vied with the canals in arousing public enthusiasm. There was a vast movement of population westward, and the Ohio River was a busy thoroughfare. All of these enterprises aroused a demand for labor, which, as we have seen, the native population would not readily supply. By the middle of the decade the stream of immigration had begun to respond, so that in 1825 the number of arrivals for the year reached the ten thousand mark for the first time since statistics had been collected. By the end of the decade the number had more than doubled. In the fifteen months ending December 31, 1832, there were over sixty thousand arrivals, and in the year 1842, 104,565—the first time the hundred thousand mark had been reached. Such an enormous increase in immigration as this could not fail to have its effect upon the social life of the nation, and to attract widespread attention. Coupled with the changing nature of industry, it brought many new problems before the American people—congestion, tenement house problems, unemployment, etc. Pauperism, intemperance, beggary, and prostitution increased.[59] For many of these evils it began to appear that the immigrants were partly responsible. Yet during the twenties it seems that the immigrants were, on the whole, in good favor. The great economic need which they filled outweighed the social burden which they imposed, but which, as yet, was only vaguely felt. The hard manual labor on the construction enterprises of the period was mainly performed by Irish laborers, who flocked over in great numbers, constituting the largest single element in the immigration stream, amounting to probably nearly half of the entire number. It was believed by many Americans, as well as by foreign travelers and observers, that the canals and railroads could never have been built without these sturdy Irishmen. They were a turbulent and reckless lot, though perhaps not wholly through their own fault. Their miserable wages were supplemented by copious supplies of whisky, with the result that the labor camps were frequently the scenes of riotous demonstrations which shocked the sensibilities of the American community.