When we last left our flax, it had been planted, grown and been harvested by being pulled up (by the roots) in roughly handful-sized bundles. That process leaves us with the stalks of the flax plants. The useful part of these is called bast, which must now be separated from the other plant fibers. Moving from the inner-most part of the plant outward, a flax stem is made up of a woody core (the pith), followed by the living cells of the plant which transport nutrients and water up the stem (the phloem and xylem), which are supported by our all important bast fibers, and then outside of the bast is the skin of the plant (the epidermis and cortex). So our task with our freshly harvested flax is to get rid of everything in this stalk that isn’t a bast fiber.
The process for this is called retting and changed relatively little during the pre-modern period. The term “retting”, related to the Dutch reten shares the same root as English “rot” and that is essentially what we are going to do: we are going to rot away every fiber that isn’t the bast fibers themselves. The first step is to dry the stalks out, at least to a certain point. Then in the most common form of retting (called “water retting”) the partially dried stalks are submerged in stagnant or slow-moving waters (because you do not want too much water-motion action on the flax washing it away). Pliny (Natural History 19.17) notes the use of weights to hold the stalks down under the water. The water penetrates into the partially dried stalks, causing the pith to expand and rupture the skin of the stalk, which permits bacteria into the stalk. That bacteria then rots away the chemicals which bind the fibers together (this is pectin, located in the cell walls of the plant cells) allowing the fibers to be separated. This process takes around two to three weeks to complete, but has to be carefully controlled and monitored; over-retting will make the bast fibers themselves too weak, while under-retting will make it more difficult to separate the fibers.
By the Roman period at least, the potential benefits of retting in warm water were already well known (Pliny, NH 19.17). There is some evidence, for instance from Staonia and Saetabis, that at least by the Roman period specially built pools fed by small channels and exposed to the sun (so they would heat up) were sometimes used to speed the process. Very fine flax was in some cases double-retted, where stalks are partially retted, removed early, then retted a second time. Alternately, in water-poor regions, retting might instead be done via “dew retting” where the stalks are instead spread evenly and carefully on either grassy fields or even on the roofs of houses (e.g. Joshua 2:6), where the action of morning dew provides the necessary moisture for bacteria to break down the pectin. Dew retting generally seems to have taken rather longer as a process.
Once retted, the flax must be dried completely. The nest step is breaking, where the pith of the stalks is broken up by being beaten, sometimes with a wooden club (Pliny mentions a particular type of mallet, a stupparius malleus, or a “tow-club”, tow being the term for short broken fibers produced in the processing of flax, for this purpose, Pliny, NH 19.17). In some places (particularly in Northern Europe) it seems that stomping on the flax by foot or having horses do so was used for this purpose. Once broken up, the pith and other fibers may be separated from the bast using a wooden knife in a process called scutching (the knife is called a scutching knife). By the 1800s, this process was assisted through the use of a swingle, essentially a board stood upright with an opening at the top where the flax could be inserted and held, while the scutcher then strikes with the scutching knife downward against the board. Scutching is a fairly rapid process; Sir George Nicholas detailing flax production in the 1800s (in The Flax-Grower (1848), 45-6) reports that a skilled worker could scutch ten to fifteen pounds of flax a day by hand, though improper retting or low-quality flax might be more difficult to process. Scutching, when completed, left a bundle of fibers (sometimes slightly twisted to hold them together), with almost all of the other plant matter removed.
All of these steps, from planting to scutching, seem to have generally been done on the farm where the flax was being cultivated. At least in the early modern period, it was only once the flax had been scutched that the bundles might be sold (Nicholas, op. cit., 47). That said, our flax is not quite ready to spin just yet. The final step is hackling (also spelled heckling), where the bast fibers are combed along a special tool (a hackling board or comb) to remove the last of the extraneous plant matter, leaving just the bast fibers themselves. The hackling board itself is generally a wooden board with several rows of nails (the “teeth”) put through it, through the earliest hackles seem to have been made of bone or else a wood board using thorns or thistle as teeth (see Barber (1992), 14 for a reconstruction). The fibers that come out of this process are generally separated into grades; the “tow” fibers are short, loose or broken fibers that come loose from the longer strands of bast during scutching or hackling; these are gathered and spun separately and typically make a lower-quality linen thread when spun. They stand in contrast to the “line” of long bast fiber strands, which after hackling form long wavy coils of fibers called stricks; the small tangles give these fibers coherence and account for part of the strength of high quality linen, once spun. Pliny comments on the roughness of the entire process, quipping that “the more roughly treated [the linen is] the better it is” (Pliny NH 19.18). Nicholas, on this point, is explicit that the two grades ought to be kept separate, so as not to lower the value of the more useful fibers (op. cit., 47).
There was a significant amount of skill in the entire process. Pliny notes that the ratio of flax input to usable fiber output was skill dependent (NH 19.18) and that a good worker could get around fifteen Roman pounds (10.875lbs, 4.93kg) of usable fiber out of fifty Roman pounds (36.25lbs, 16.44kg) of raw flax. Nicholas agrees, noting that hand scutching skill was deemed sufficiently important for experienced scutchers to be sent to train workers elsewhere in the best methods (op. cit. 47). Pliny concludes on this basis that producing flax was a sufficiently skilled job as to befit free men (Nicholas also assumes a male worker, at least with his pronouns; he is explicit that breaking was done by men, though with women or children assisting by placing and retrieving the bundles of flax as they are broken), though it seems that much of this work was also done by women, particularly scutching and hackling. In each case it seems fairly clear that this work was done mostly on the flax farm itself, by many of the same people living and working on that farm.
The final result of all of this processing are bundles of individual flax bast filaments which are now quite smooth, with a yellow, “flaxen” color (though early pulled, very fine flax may be a quite pale yellow, whereas utilitarian late-pulled flax is a deeper near-brown yellow), ready to spin. We’ll deal with color treatment in a later post, but I should note here that linen is notoriously difficult to dye, but can be bleached, for instance by exposing the fibers to the sun during the drying process.
Bret Devereaux, “Collections: Clothing, How Did They Make It? Part II: Scouring in the Shire”, A Collection of Unmitigated Pedantry, 2021-03-12.