third edition it was retitled A Treatise on the Decorative Parts of Civil Architecture. It included ideas from the works of many 16th- and 17th-century Italian architects then still little known in Britain. His influence was also transmitted through a host of younger architects trained as pupils in his office, including Thomas Hardwick (1752-1825), who helped him build Somerset House and who wrote his biography.

He was the major rival of Adam in British