The first article in a series by Paul O'Connor introducing double weave on a rising-shed (jack) loom, beginning with four harnesses and leading toward six and eight. It outlines four ways of treating the two layers (separate layers, joined at one selvage, tubes, and pickup), then covers straight-draw threading, sett, tieups and treadling for two separate layers. It closes with interchanging layers for a checkerboard effect and a skeleton tieup for a four-harness loom with six treadles. Figures show the threading, a layer cross section, and tieup diagrams.