Tartan — where it appears
Named by 3 essays across one field — each of them below, with the objects they name alongside it.
A check is two stripes and a tartan is one
A tartan is quoted as one sett of thread counts because the warp and the weft carry the same order. That is said to make it symmetric about its diagonal, and the arithmetic says it cannot be — the ceiling is three quarters, and a 2/2 twill reaches one half.
A weft stripe is counted in pairs of picks
A warp's colour order is laid out once at warping and the loom never has to think about it. A weft's is thrown, one pick at a time, by shuttles that cross the cloth and stay where they land. On a loom with boxes at one side that makes every coloured band an even number of picks; with boxes at both sides it admits odd bands and pays for them in shuttles; and a tartan, which uses one order in both directions, is designed for its weft whether its designer knew it or not.
The finest colour-and-weave effects need the rarest loom
A houndstooth, a shepherd's check and a gun club check are thrown by the cheapest shuttle loom there is. A hairline, an end-and-end and a log cabin are thrown by none — a colour on every other pick is thrown from the same side every time, so its shuttles pile up at the far end of the loom and never come back. The dividing line is the parity of the bands and nothing else, which is why it survives the fact that no two sources agree about how wide a shepherd's check is.
Named alongside it
The objects these essays reach for when they reach for this one.
CensusCheckColour and weaveColour orderPivoted settStripeBalanceBlind intersectionCollisionFaceShaftsTranspose