Another difficulty was that the Constitution of the State of New York limited the debt-incurring power of the city. The capacity of the city to undertake the work had been much discussed in the courts, and the Supreme Court of the State had disposed of that phase of the situation by suggesting that it did not make much difference to the municipality whether or not the debt limit permitted a contract for the work, because if the limit should be exceeded, "no liability could possibly be imposed upon the city," a view which might comfort the timid taxpayers but could hardly be expected to give confidence to the capitalists who might undertake the execution of the contract. Various corporations, organized during the thirty odd years of unsuccessful attempts by the city to secure underground rapid transit, claimed that their franchises gave them vested rights in the streets to the exclusion of the new enterprise, and they were prepared to assert their rights in the courts. (The Underground Railroad Company of the City of New York sought to enjoin the building of the road and carried their contest to the Supreme Court of the United States which did not finally decide the questions raised until March, 1904, when the subway was practically complete.) Rival transportation companies stood ready to obstruct the work and encourage whomever might find objection to the building of the road. New York has biennial elections. The road could not be completed in two years, and the attitude of one administration might not be the attitude of its successors. The engineering difficulties were well-nigh appalling. Towering buildings along the streets had to be considered, and the streets themselves were already occupied with a complicated network of subsurface structures, such as sewers, water and gas mains, electric cable conduits, electric surface railway conduits, telegraph and power conduits, and many vaults extending out under the streets, occupied by the abutting property owners. On the surface were street railway lines carrying a very heavy traffic night and day, and all the thoroughfares in the lower part of the city were congested with vehicular traffic. Finally, the city was unwilling to take any risk, and demanded millions of dollars of security to insure the completion of the road according to the contract, the terms of which were most exacting down to the smallest detail.