The era of strikes which set in with the contraction of trade in 1857 proved how fallacious had been these hopes. The building trades, in particular, had remained less affected than the Engineers or the Cotton Operatives by the change of tone. The local branches of the Stonemasons, Bricklayers, and other building trade operatives, often against the wish of their Central Committees, were engaged between 1853 and 1859 in an almost constant succession of little strikes against separate firms, in which the men were generally successful in gaining advances of wages.[370] These years were, moreover, notable for the recognition in the provincial building trades of “working rules,” or signed agreements between employers and workmen (usually between the local Masters’ Associations and the Trade Unions), specifying in minute detail the conditions of the collective bargain. Without doubt the adoption of these rules was a step forward in the direction of industrial peace; but, like international treaties, they were frequently preceded by desperate conflicts in which both sides exhausted their resources, and learnt to respect the strength of the other party. With the depression of trade more important disputes occurred. During 1858 fierce conflicts arose between masters and men in the flint glass industry and in the West Yorkshire coalfield. The introduction of the sewing-machine into the boot and shoemaking villages of Northamptonshire led to a series of angry struggles. But of the great disputes of 1858 to 1861, the builders’ strike in the Metropolis in 1859-60 was by far the most important in its effect upon the Trade Union Movement.