Weigle, Oscar: Color Scheme ©1949 Oscar Weigle Softcover, folded manuscript, 8.5x11", 5 pages

Image courtesy ConjuringArts

Comments: Effect inspired by Paul Curry's Out of This World and a concept by Bob Hummer.
Spectator brings out face up and face down cards, but all face ups are of one color and face downs of the other.

Contents (from book):

1 Introduction
1 Effect
1 Setup
2 Procedure
3 Addenda: additional suggestions
3 - Varying Number of Cards
3 - Shuffling
4 - Same Principle in Spectator's Hands
4 - Additional Mixing
4 - Martin Gardner Idea
5 - Clayton Rawson Ideas