Squirrel-Hair Quill Pencils and Hog-Bristle Brushes (Cennini, c. 1400)

"In painting, two kinds of brushes are necessary, namely, minever and hog's bristles."

Use dressed (cured) grey-squirrel tails, never raw ones. To keep moths off and the hairs from falling out, stick them tight into kneaded clay or chalk and hang them up; wash them in clean water before use.

For a soft gilding pencil, draw the longest hairs from the tips of six or eight tails. For other brushes take the straightest, stiffest hairs from the middle of the tail. Make small bundles, soak them in a glass of clear water, squeeze each with the fingers, and trim them with scissors. Lay the points even and tie each with waxed thread or silk, two knots.

Take a quill (vulture, goose, hen or dove) to suit the bundle, cut off its end, and push the hairs in, squeezing in as many as you can: the firmer and shorter the brush, the finer work it does. Scrape a small stick of maple, larch, chestnut or other good wood into a smooth spindle that fits tightly into the quill, about a span long. For flat washes blunt the brush a little with scissors and rub it on a smooth stone; keep others to a perfect point for outlines, and some very small for fine work.

Take bristles of a white domestic pig (better than black). Bind a pound of them on a large stick and use it to whitewash and wash walls until the bristles soften.

Unbind the wall brush and make the bristles up into brushes of all sizes, some blunt (all hairs one length), some pointed. Bind each bundle with a double waxed thread, push the pointed end of a stick into it, bind it evenly for half the length of the bristles and then on down the stick.

From Cennino Cennini, **Il Libro dell'Arte** (c. 1400), translated by Christiana J. Herringham as **The Book of the Art of Cennino Cennini** (1899), chaps. 64-66 (checked on the archive.org scan bookartcenninoc01herrgoog, pp. 52-54). One word in the manuscript, what the wall brush is tied with, is defaced. Herringham explains minever as the grey squirrel. The metric figures and the smooth stone in place of his porphyry are ours.