The steel manufacturers may be grouped into four general types with respect to their careers, whether those careers were mainly in the steel industry or not. A career has been described as ‘independent’ if the subject founded or helped to found the firm which he controlled in the steel industry, or if he had established and led a firm in another business before he entered the steel industry. The second category comprises men whose major work was in their fathers' firms, whether that firm was in the steel industry or not, and also those who invested in going concerns and whose industrial careers were mainly a product of such investment. Thus these are the men who, in Marshall's terms, might be expected to have ‘profited by traditions as to things, methods and persons’. The third group, salaried administrators, may have held a few shares in a limited company, or even have become partners, but their careers were primarily as employees of limited companies and partnerships and they reached the top by virtue of executive experience rather than investment. Steel manufacturers who had spent most of their lives practising in an independent profession make up the fourth group. In Table 19 the steel manufacturers in each period are classified into these four main career types, to which reference will be made throughout this chapter.