In this letter, Captain Trewren informs F. A. Legg of the events which took place at the recent setting day at Mona Mine. The trouble began when a bargain which had been refused by two Welsh miners was taken by two Cornishmen, 'in consequence of which the greater part of the miners have refused to work and say they will not resume their work until such time as these men are expelled or driven from the mine'. Trewren explains that on 6 April, 'a great number of the miners gathered around' the Cornishmen with the aim of 'compelling them by force to leave'.