Taking a photograph nowadays can be as easy as whipping out your phone and gleefully snapping away. But pictures weren’t always such a throwaway commodity. No, in the 19th and 20th centuries, taking a crisp shot could demand hours of work and a litany of hugely expensive equipment. The photographs of yore were much toiled-over, then. And the following images in particular are true masterpieces, as they capture crucial moments in the history of human civilization – from NASA’s lunar missions to the construction of the Statue of Liberty.