Introduction by Mr. Dunican: 'The design and construction of the first phase of the Stock Exchange rebuilding is in my opinion a working example of the ideas embodied in my paper, "The Art of Structural Engineering", which I presented to the Institution in
March 1966. At that time I said, perhaps rather too obviously, that a structure of a building must satisfy four main conditions. It must stand up, it must be capable of being built economically and within the means available, and it must suit the building. I also quoted Eduardo Torroja, who said: "Structural design is concerned with much more than science and techniques, it is also very much concerned with art, common sense, sentiment, aptitude, and enjoyment of the task of creating opportune
outlines to which scientific calculations will add finishing touches, substantiating that the structure is sound and strong in accordance with requirements."