In some callings there are such differences of pay and social position that even if all their members could be brought together they would not mix. Thus on the stage an actor may be a highly accomplished gentleman with a title, who plays Hamlet, or a lady who is an aristocrat and a Dame of the British Empire, and plays Portia: both of them receiving weekly salaries counted in hundreds of pounds. With them are working every night actors and actresses who never utter a word, because, if they did, their speech would betray the fact that, far from being the court lords and ladies they are dressed up to look like, they are not earning as much as the carpenters who shift the scenes. It is even possible for an acrobat or clown to be more highly paid than Hamlet, and yet in private life be so illiterate, and have such shocking table manners, that the titled Hamlet could endure neither his conversation nor his company at dinner. For this reason a union of actors is difficult: a class split is inevitable. Union is possible only in trades where the members work together in large bodies; live in the same neighborhoods; belong all to the same social class; and earn about the same money. The miners in the coalfields, the cotton spinners in the factory towns of Lancashire, the metal smelters and fitters in the Midlands, were the first to form enduring and powerful unions. The bricklayers, masons, carpenters, and joiners who come together in the building trades were also early in the field with attempts at unionism. Under the stress of some intolerable oppression they would combine to make the employers see their situation in some particular point; and when they had carried that point, or were defeated, the union would dissolve until another emergency arose. Then they began to subscribe to form little insurance funds against unemployment, which obliged them to keep the union together; and in this way the unions grew from momentary rebellions into permanent Trade Unions of the kind we know.