The Classical Language of Architecture is a 1965 compilation of six BBC radio lectures given in 1963 by Sir John Summerson. It is a 60-some page discussion of the origins of classical architecture and its movement through Antiquity, Renaissance, Mannerist, Baroque, Neoclassical, and Georgian periods. A discussion of the rules and elements in classical terms of the Orders, architectural harmony of design, are included. In 2015 it remains in print in several countries, in illustrated editions of about 144 pages.
Summerson, John. The Classical Language of Architecture. in UK now Thames and Hudson World of Art series, etc. In US Boston: MIT Press, 1965, and other editions.