COLUMBANI, PLACIDO, Italian architectural designer, who worked chiefly in England in the latter part of the 18th century. He belonged to the school of the Adams and Pergolesi, and like them frequently designed the enrichments of furniture. He was a prolific producer of chimney-pieces, which are often mistaken for Adam work, of moulded friezes, and painted plaques for cabinets and the like. There can be no question that the Eng lish furniture designers of the end of the 18th century, and especially the Adams, Hepplewhite and Sheraton, owed much to his graceful, flowing and classical conceptions, although they are often inferior to those of Pergolesi. His books are still a valuable storehouse of sketches for internal architectural decoration. His principal works are :—Vases and Tripods (177o) ; A New Book of Ornaments (17 7 5) ; A variety of Capitals, Friezes and Corniches, and how to increase and decrease them, still retaining their proportions (1776).