Very early the United Mine Workers established a reputation for strict adherence to agreements made. This faithfulness to a pledged word, which justified itself even from the standpoint of selfish motive, in as much as it gained for the union public sympathy, was urged upon all occasions by John Mitchell, the national President of the Union. The first test came in 1899, when coal prices soared up rapidly after the joint conference had adjourned. Although they might have won higher wages had they struck, the miners observed their contracts. A more severe test came in 1902 during the great anthracite strike.[57] A special union convention was then held to consider whether the bituminous miners should be called out in sympathy with the hard pressed striking miners in the anthracite field. By a large majority, however, the convention voted not to strike in violation of the agreements made with the operators. The union again gave proof of statesmanly self-control when, in 1904, taking into account the depressed condition of industry, it accepted without a strike a reduction in wages in the central competitive field. However, as against the miners' conduct in these situations must be reckoned the many local strikes or "stoppages" in violation of agreements. The difficulty was that the machinery for the adjustment of local grievances was too cumbersome. In 1906 the trade agreement system encountered a new difficulty in the friction which developed between the operators of the several competitive districts. On the surface, the source of the friction was the attempt made by the Ohio and Illinois operators to organize a national coal operators' association to take the place of the several autonomous district organizations. The Pittsburgh operators, however, objected. They preferred the existing system of agreements under which each district organization possessed a veto power, since then they could keep the advantage over their competitors in Ohio and Indiana with which they had started under the original agreement of 1898. The miners in this emergency threw their power against the national operators' association. A suspension throughout most districts of the central competitive field followed. In the end, the miners won an increase in wages, but the Interstate agreement system was suspended, giving place to separate agreements for each district.