Men who in the following decade led the Pacific railway agitation promoted the Illinois Central idea in the years immediately preceding 1850. Both Breese and Douglas of Illinois claimed the parentage of the bill which eventually passed Congress in 1850, and by opening the way to public aid for railway transportation commenced the period of the land-grant railroads. Already in some of the canal grants the method of aid had been outlined, alternate sections of land along the line of the canal being conveyed to the company to aid it in its work. The theory underlying the granting of alternate sections in the familiar checker-board fashion was that the public lands, while inaccessible, had slight value, but once reached by communication the alternate sections reserved by the United States would bring a higher price than the whole would have done without the canal, while the construction company would be aided without expense to any one. The application of this principle to railroads came rather slowly in a Congress somewhat disturbed by a doubt as to its power to devote the public resources to internal improvements. The sectional character of the Illinois Central railway was against it until its promoters enlarged the scheme into a Lake-to-Gulf railway by including plans for a continuation to Mobile from the Ohio. With southern aid thus enticed to its support, the bill became a law in 1850. By its terms, the alternate sections of land in a strip ten miles wide were given to the interested states to be used for the construction of the Illinois Central and the Mobile and Ohio. The grants were made directly to the states because of constitutional objections to construction within a state without its consent and approval. It was twelve years before Congress was ready to give the lands directly to the railroad company. The decade following the Illinois Central grant was crowded with applications from other states for grants upon the same terms. In this period of speculative construction before the panic of 1857, every western state wanted all the aid it could get. In a single session seven states asked for nearly fourteen million acres of land, while before 1857 some five thousand miles of railway had been aided by land grants. When Asa Whitney began his agitation for the Pacific railway, he asked for a huge land grant, but the machinery and methods of the grants had not yet become familiar to Congress. During the subsequent fifteen years of agitation and survey the method was worked out, so that when political conditions made it possible to build the road, there had ceased to be great difficulty in connection with its subsidy.