In this work there was grouped around him a score of men.—W. Phillips
A number of jeweled paternosters was attached to her girdle.—Froude.
Something like a horse load of books has been written to prove that it was the beauty who blew up the booby.—Carlyle
This usage, like some others in this series, depends mostly on the writer's own judgment. Another writer might, for example, prefer a plural verb after number in Froude's sentence above.
Singulars connected by or or nor.
(3) When the subject consists of two or more singular nouns connected by or or nor; as,—
It is by no means sure that either our literature, or the great intellectual life of our nation, has got already, without academies, all that academies can give.—M. Arnold.
Jesus is not dead, nor John, nor Paul, nor Mahomet. —Emerson.
Plural form and singular meaning.
(4) When the subject is plural in form, but represents a number of things to be taken together as forming one unit; for example,—