At another time a provision was inserted in the appropriation law establishing the 8-hour day law for American workers on the canal. A fight was made by the American Federation of Labor and other organizations to make it apply to the common laborer as well as to the Americans, but this was unsuccessful. The 8-hour provision did not work well, since the foremen and superintendents were permitted to stop work after 8 hours, while the laborers under them had to work an hour longer. This was later rectified by providing that the 8-hour law should not affect foremen and superintendents in charge of alien labor; and thus was overcome the difficulty of having an army of common laborers at work an hour or so each day without superintendence or direction. In 1906 it was provided by a joint resolution of the Senate and House that the purchase of material and equipment for use in the construction of the canal should be restricted to articles of American production and manufacture, except in cases where the President should deem prices extortionate or unreasonable. This provision undoubtedly increased by many millions of dollars the cost of the machinery with which the canal work was executed. While some dredges and other equipment were purchased in Europe, foreign purchases were the exception rather than the rule. When bids were submitted there were times when European prices of dredges were placed at less than $700,000, while American prices for the same dredges would amount to more than $1,000,000. When there were such marked difference in bids the awards were made to the European manufacturers. Although the construction of the canal was authorized by the Spooner Act in 1902, it was not until 1906 that Congress expressed its views in legislation on the question of the type of canal that should be built. It was then that it declared the canal should be of the general lock type proposed by the minority of the board of consulting engineers, which was a complete approval of the plans urged by President Roosevelt. In order to make certain this decision as to the type of canal, a provision was incorporated in the appropriation bill of that year, setting forth that no part of the sums therein appropriated should be used for the construction of a sea-level canal. Congress was always willing to aid the engineers in meeting unforeseen contingencies by giving them unusual liberties in the application of moneys appropriated. It was provided that as much as 10 per cent of any appropriation might be used for any of the other purposes for which money was appropriated, thus allowing the necessary leeway to insure a systematic progress of the work throughout all its features. This provision many times came to the rescue of the chief engineer, when he found that more money was needed at one point and less at another than had been estimated 16 or 18 months before.