The specialisation of function in a large town is, however, qualified in two ways. The strong local organisation of a staple trade requires the grouping round it of a number of secondary or auxiliary trades. In large textile towns the manufactures of textile machinery, and of subsidiary materials, are found. The machine-making of Manchester is one of its most important industries, furnishing the neighbouring textile towns. Leeds is similarly equipped for the woollen trade. This is one of the respects in which the superior development of the English cotton industry over the continental ones is indicated. In Alsace alone of the continental centres has the concentration of industry advanced so far as to furnish a local machine industry specially devoted to cotton machinery. Germany is still mainly dependent upon England for her machines.[121] So likewise with regard to co-ordinate trades, there is an advantage in the leading processes being grouped in local proximity, though they are not united in the same business. Thus we find dye-works and the various branches of the clothing trade largely settled in the large textile towns, such as Leeds, Bradford, Manchester, Bolton. The unit of local specialisation is thus seen to be not a single trade, but a group of closely allied trades, co ordinate, dependent, and derivative. Round some large industries in which men find employment minor parasitic industries spring up stimulated by the supply of cheap abundant labour of women and children. In metal and machine towns such as Birmingham, Dudley, Walsall, in Newcastle-on-Tyne, and other shipbuilding towns, where the staple industries are a masculine monopoly, textile factories have been planted. The same holds of various mining villages and of agricultural villages in the neighbourhood of large textile centres. There is in the midland counties a growing disposition to place textile factories in rural villages where cheap female labour can be got, and where the independence of workers is qualified by stronger local attachments and inferior capacity of effective trade union organisation. As textile work passes more and more into the hands of women,[122] this tendency to make it a parasitic trade thriving upon the low wages for which women's labour can be got where strong and well-paid male work is established, will probably be more strongly operative.