DescriptionsToolsOnly two tools are required, the compass and the straightedge. They work on a flat surface (a plane). Compass, also called a pair of compasses: Mechanically, this is nothing more than two members, usually called 'legs,' joined by a pivot, or hinge. The legs may be straight or curved or otherwise, so long as they are rigid. The joining may be at the ends of the legs, or at some point midway along their lengths. If midway, the compasses may be 'proportional,' the extensions at one end proportional to the extensions at the others. Functionally, the compass is used for drawing circles or parts of circles ('arc'), and to 'take' measures. In drawing circles or portions of them, the end of one leg (its 'foot') is fixed in place, and the other end (the other 'foot') moves along a plane surface, marking its path. In taking measures, the feet of the compass are placed at the points to be measured. Straightedge: Mechanically, this is nothing more than a piece of flat material having one edge that is straight, that is to say, extending uniformly in a single direction. Functionally, a straightedge guides the path for a moving point for making the direct (shortest) path between two points. ConfigurationsThe four common configurations pair up to a large extent with the materials and the contexts of the artifacts.
Three of these—circle, ringed cross, and rectangle—are configurations constructed on a plane surface (twodimensional). All three can be seen. The configuration of segmented lineal extensions (onedimensional) cannot be seen, even if the segmentations themselves are a conspicuous visual part of the text; it can be recognized only in the relations among the counts of metrical lines in the segments. All four configurations depend for their creation or their development on setting lines at right angles. That is obvious in the rectangle forms and the crosses (ringed and otherwise). In the circular designs and lineal extension plans it may not appear in structural lines: but it always appears in the sources of the ratios among the lengths and the distancing of the principal lines. RatiosThe ratios which govern the finest Insular designs incorporate integers 1 and 2 together with 'geometric' measures produced with 1 and 2 in rightangle configurations  √2, √3, √5 How these ratios are set up in Insular designing is the key to understanding the coherence of the designs. They are described and illustrated in detail with the Guide. GuideHere in oldfashioned print format is a practical guide to the Coherent Geometry of Insular Art. Sections 3 and 4  Setting the Ratios, and Creating the Designs  are essentially demonstrations. Sections 1, 2, and 5 give some background to understanding the nature of Insular designing.

DemonstrationsTara Brooch (QuickTime) Dunadd Motifpiece (QuickTime) Design Method Demonstration for Lunula (QuickTime) Guthlac A, Commodular Relations Among the Parts (QuickTime) More Information 