An article by Ralph Griswold on using power sequences (squares, cubes and higher powers) reduced by modular arithmetic and normalized to produce threading and treadling sequences for weaving drafts. It explains residue sequences, their periods, straight draws, and the number of distinct values (shafts or treadles needed). It counts distinct sequences for powers 2 to 32 and moduli 2 to 64. Appendix A tabulates the properties of the normalized residue sequences, and Appendix B is a long series of graphical drawdown-style bitmap patterns derived from them.