The chapter re-examines the works of Mill, Marshall and Jevons. In different ways they extended DoLfg analysis, enhancing its equilibrium flavour. The latter two also attempted to add inputs to the analysis beyond labour. Smith’s DoLop analysis caught their attention, too. Mill gave several examples of such division, showed awareness of the importance of inter-industry connections and alluded to the complexity of learning processes. Marshall and Jevons (in The Coal Question) were likewise strongly inspired by it, subtly admitted its implications for uneven development and referred to England’s trading partners as its ‘tributaries’. Like Smith and Ricardo, Mill employed DoLfg-based reasoning to undercut the case for trade protection. He did pen a qualified endorsement for protecting an infant industry and at no place therein did he incorporate inter-industry connections. Marshall empathised with that endorsement. But unlike Mill, he referred to protection of nascent industries and was aware of the importance of having auxiliary industries properly established and organised. Jevons’ strong admiration of Smith’s DoLop analysis is nowhere to be found in his Theory of Political Economy.