John W. Macklem (1867-1948) began working for E.I. du Pont de Nemours & Company as an errand boy at a young age and remained with the company his entire career. E.I. du Pont de Nemours & Company is a chemical company more commonly referred to as the DuPont company. This collection comprises photographs of buildings and scenes in DuPont Company explosives manufacturing plants along the Brandywine Creek near Wilmington, Delaware, including the Eleutherian Mills (or Upper) yard, the Upper Hagley yard, and the Lower Hagley yard.