After practicing law in his hometown for five years with his father's firm, he accepted a position with steel manufacturer M. A. Hanna Company in 1917.
The M. A. Hanna Company closed Seventh Shaft but retained Sixth Shaft and the breaker into the 1960s.
In 1929, Weir merged Weirton Steel with Detroit's Michigan Steel and Cleveland's M. A. Hanna Company to form National Steel Corporation.
American Broadcasting Company | Fox Broadcasting Company | Ford Motor Company | The Walt Disney Company | Royal Shakespeare Company | Hudson's Bay Company | East India Company | Hanna-Barbera | Dutch East India Company | McKinsey & Company | H. J. Heinz Company | William Hanna | Company | Peninsular and Oriental Steam Navigation Company | company | Bad Company | production company | Three's Company | Shell Oil Company | Goodyear Tire and Rubber Company | Glenn L. Martin Company | The Coca-Cola Company | Southern Pacific Transportation Company | Pullman Company | Marconi Company | Canon (company) | Victor Talking Machine Company | Negro Ensemble Company | Little, Brown and Company | Firestone Tire and Rubber Company |