Let be the first uncountable ordinal. A result of Rudin implies that bounded operators on the Banach space of continuous functions on the ordinal interval have a natural representation as -matrices. Loy and Willis observed that the set of operators whose final column is continuous when viewed as a scalar-valued function on defines a maximal ideal of codimension one in the Banach algebra of bounded operators on . We give a coordinate-free characterization of this ideal and deduce from it that contains no other maximal ideals. We then obtain a list of equivalent conditions describing the strictly smaller ideal of operators with separable range, and finally we investigate the structure of the lattice of all closed ideals of .