A on Lap Steel: What the Chart Leaves Out
24 types on one root, for the space between two bars.
Every scale type this site maps, rooted on A and laid onto this reader. A chart is silent about all of them by design — it prints the harmony a player cannot guess and trusts the room for the rest — so this is the half of the page the numbers deliberately leave blank.
With a bar instead of fingers, a scale is a set of stopping places rather than a set of grips, and the slide between two of them is as much of the line as either end.