[8] derecta plumbo: for securing greater regularity, a thin, circular plate of lead guided by a ruler was used to draw lines for the writing, and to mark off the space reseived for margins. derecta, like aequata, modifies omnia, and is written rather than directa because motion in a single, fixed direction is indicated; cf. Catul. 63.56 “derigere aciem” .