▁his ▁training ▁with ▁a ▁six - month ▁post ▁as ▁an ▁engine ▁driver ▁on ▁the ▁Berlin - H amb urg ▁Railway . ▁Between ▁ 1 8 4 7 ▁and ▁ 1 8 5 1 ▁he ▁was ▁the ▁chief ▁mechanical ▁engineer ▁( M as ch inen meister ) ▁of ▁the ▁Mag de burg - W itten ber ge ▁Railway . ▁ ▁With ▁the ▁support ▁of ▁his ▁family ▁he ▁bought ▁the ▁site ▁at ▁Ch aus se est ras se ▁ 2 0 , ▁which ▁was ▁border ed ▁to ▁the ▁south ▁by ▁Invalid en str asse ▁and ▁to ▁the ▁east ▁by ▁the ▁Berlin - St ett in ▁Railway . ▁Under ▁the ▁terrain ▁of ▁the ▁latter ▁is ▁the ▁under ground ▁S - B ahn ▁station ▁called ▁Nord bahn hof . ▁ ▁On ▁ 3 ▁October ▁ 1 8 5 2 ▁he ▁founded , ▁together ▁with ▁the ▁then ▁Berliner ▁G ieß ere ime ister ▁N it sche ▁the ▁Schw art zk op ff ▁and ▁N it sche ▁Iron ▁Found ry ▁& ▁Engineering ▁Works ▁( E is eng ieß erei ▁and ▁Mas ch inen fab rik ▁Schw art zk op ff ▁and ▁N it sche ) ▁in ▁Berlin , ▁from ▁which ▁the ▁Berliner ▁Mas ch inen bau ▁AG ▁vorm . ▁L . ▁Schw art zk op ff ▁emer ged ▁in ▁ 1 8 7 0 . ▁Schw art zk op ff ▁wanted ▁above ▁all ▁to ▁expand ▁the ▁engineering ▁works , ▁whilst ▁N it sche ▁preferred ▁to ▁concent rate ▁on ▁art istic ▁cast ings . ▁So ▁Schw art zk op ff