(p. 14) Alberti begins by talking about walls, and then says a row of columns is simply “a Wall open and discontinued in several Places;” he says the column supports the roof, and that columns are the most beautiful of the architectural elements; here, he’ll address what columns have in common, and later he’ll discuss their differences.
(p. 14) all columns rest on a plinth (or dye), which supports a base, which supports the column, which is topped by a capital; columns are usually widest at the base, and taper toward the top; Alberti says the column was invented simply to hold up the roof, but men sought to make their buildings “immortal and eternal,” so they embellished columns with architraves, entablatures, etc.