(The following article is part of A Layman’s Guide to Ancient Life)
Rawhide is a hard, translucent form of animal skin that has been cleaned of all fur, meat and fat and dried in the sun, often while stretched over a frame. Fur can be loosened by soaking the hides in solutions of water and wood ash, lime, urine, or by simply letting the hides putrefy (alternately, the fur can be left on). The skins are then scraped with flat or ridged utensils.
Rawhide can be shaped before it has dried completely, and can be rendered more pliable by rubbing with oil, or by repeated bending, rubbing, or chewing. Rubbing with oil also waterproofs the hide to a degree, but rawhide will quickly soften if left wet. Rawhide is commonly used for the soles of sandals and boots, and other items where hardness is a desired trait.
Leather is the tanned form of rawhide, and is far more pliable than untanned skins. After being cleaned of fur, meat and fat (fur can be left on if desired), skins are bated (made more pliable) by pounding, or by soaking with a mixture of water and manure, often that of dogs or birds, and kneading by hand or foot. Skins are then treated with tanning agents to turn them into leather.
One method of tanning involves the use of emulsified fats or oils, most commonly brains boiled in water, though eggs, milk and tallow can also be used. The fats are then worked into the skin by hand in successive coats. After the skin has dried it can be bent or stretched to increase its pliability; brain-tanned leather is known for its exceptional softness.
Vegetable tanning involves creating a solution of water and tannin-containing plants (usually bark of trees such as oak, spruce, fir, or birch). The dried plant material is crushed or ground into a coarse powder, then soaked, simmered or boiled in water. Higher water temperatures darken the tannin, while cold water produces a lighter color. Over the course of weeks to months, hides are soaked in progressively stronger tannic solutions; letting the hide tan completely produces a stiffer leather.
There are various alternative tanning methods; smoke tanning is done by burning aldehyde-containing plant material, such as green alder or tamarack. Mineral tanning (tawing) can be done with alum salts, but the material is not as supple and will revert to rawhide if soaked in water. Hides can be smoked after tanning, which can prevent stiffening if wet, deter insects and darken the color of the hide. Leather can be carved and stamped, and while leather can develop a variety of colors from the tanning process, it can also be colored with dyes during the tanning process. Regularly oiling leather improves its water resistance and suppleness.
There are numerous naturally occurring dyes from mineral, vegetable and animal sources. Yellow ochre, red ochre and umber are earth pigments found in rock and clay; orpiment and azurite are minerals which can be ground into dyes. Vegetable dyes can be sourced from a wide array of plant materials – grasses, leaves, berries, flowers, roots, bark, wood and lichen among others. Examples of vegetable dyes include acacia, alder, alkanet, black walnut, bloodroot, cutch, dogwood, henna, indigo, juniper, madder, mulberry, onion, saffron, sagebrush, sumac, turmeric, weld and woad. Less common dyes were sourced from insects and mollusks, such as kermes, cochineal, lac, murex, and cuttlefish. In most cases dye sources are dried and ground into powder before being boiled in water to create a liquid dye, although dyes from animal sources often required more a complex extraction process.
Most natural dyes are not color-fast, and fade quickly when washed or exposed to sunlight – mordants are substances which fix dyes to fibers. Mordanting, the process by which a mordant is fixed to a fiber, involves soaking or simmering the fiber or yarn in the mordant solution, and is usually done before dyeing. Common mordants include salt, vinegar, urine, wood ash, club moss, tannin-containing barks and plants, acidic fruits, iron, copper, alum, and cream of tartar. In the case of metals, the dyeing vessel itself could be the mordant. Mordants themselves can lend color to textiles (iron darkens colors) and often have specific applications (indigo was fermented exclusively with urine). Alkaline mordants (such as tannin) are used on vegetable fibers, while wools are more receptive to acids. In general, dyes tend to adhere more strongly to animal fibers than to plant fibers, while substantive dyes (such as indigo, kermes and murex) do not require a mordant to fix.
Textiles can be dyed as raw fiber, yarn-dyed (after being spun) or piece-dyed (dyed after being woven). Yarn-dying is the most common method, as it tends to produce more uniform color saturation than piece-dying, and avoids the difficulty of spinning fibers containing mordanting sediments. The basic process of dyeing requires soaking or boiling the dye in water, adding the textile to be dyed to the resulting solution, and soaking or simmering for an extended period, which could range from hours to weeks. Often the dyeing recipes for specific colors were complex, involving multiple stages of mordanting, dying, drying and washing, as well as using additional materials (such as ash, chalk, flour, milk, dung, blood, or oil).
Overdyeing, the process of dying fabrics multiple times to combine shades, was used to create a wider variety of colors than could be created from a single dye source. Resist dyeing is a form of piece-dying that involves applying wax, starch or clay to fabrics to prevent the dyes from penetrating completely. The fabric is then boiled, washing out the wax or starch and leaving behind patterns of varying shades. Alternately, the fabric can be soaked in wax, which is then scratched off to create patterns before dyeing. Tie-dying produces similar results, albeit with less accuracy.
Some textiles (particularly linen) were bleached white. Often simply drying textiles under direct sunlight was sufficient to remove their color. Cloth could be rubbed with natron or gypsum, or bathed in burning sulfur fumes to further bleach the fabric.
Spinning was a time-consuming part of the textile production process; in urbanized societies the demand for yarn was such that nearly every household took part in its production, and in many societies it comprised the majority of women’s work.
Hand spinning is performed by twisting fiber between the fingers or rolling it against the body or a flat surface; the yarn is then fixed to a weight which is spun to further twist the fibers. The process is laborious and produces a yarn that is coarser and weaker in comparison to more modern methods.
The spindle is a weighted rod with which fiber is spun; drop spindles are suspended by spun yarn, while suspended spindles rest on a surface. Cleaned and prepared fibers are held by hand or wrapped around a distaff, a rod or comb used to hold unspun material. The fiber is looped around the spindle (which often included a notch or hook to help hold the yarn), which is twirled as the fibers are drawn out. The spun yarn is then looped around the spindle for storage. The strength and thickness of yarn can be controlled by the amount of spin and the rate at which the fiber is drawn out.
Weaving at its most basic is performed by drawing parallel strings taut on a loom, then weaving strings over and under by hand at right angles. The taut strings are known as the warp, while the woven strings are known as the weft. A heddle is a rod or divider used to raise the warp strings to create a passage for the weft. Yarns of multiple colors can be used in the weft to create intricate patterns, including elaborate tapestries. The quality of fabric produced is determined by the quality of yarn, the number of strings used, and the overall skill of the weaver.
The ground loom or horizontal loom is a simple, portable loom most often used by nomadic peoples. The warp is fastened to two horizontal rods – one fastened to stakes driven into the ground, the other drawn taut by the weaver, who sits on the ground. The backstrap loom is very similar in design to the ground loom, being comprised of two horizontal rods with which draw the warp taut. One end of the backstrap loom is fastened to a point several feet above the weaver (such as a stake or wall), while the other end is fixed to a loop drawn around the weaver’s back. In this arrangement the weaver simply leans back to provide tension.
While complex and quality textiles can be woven with these methods, both ground and backstrap looms limit the size of textiles to the area which a seated weaver can reach with their arms; usually no more than several feet wider than their body.
Vertical looms hold the warp perpendicular to the ground, and are built with heavier frames. The two-bar loom consists of two beams of wood on a rectangular standing frame. The warp is fastened to the beams and the beams are turned until the yarn is drawn taut. The warp-weighted loom is a vertical loom in which the warp is held taut by hanging weights. The width of fabrics on vertical looms is limited only by the size of the loom; for larger looms, it was common for multiple weavers to work on a single fabric simultaneously.
Sewing is the process of fixing fabrics together with loops of thread (stitches), performed with a needle and string. In its earliest forms, skin was stitched together with bone or wood needles and gut or sinew string; more modern sewers use metal needles (usually copper or bronze) and spun yarn. There are several stitches, or loop styles, which can be used in sewing – the running stitch, chain stitch, backstitch, and cross stitch are the most common.
Knitting is the process of creating cloth through stitching. Flat knitting creates flat cloth, while circular knitting can create rounded shapes or tubes (such as hats, socks or glove fingers). Knitting needles are longer and less sharp than sewing needles, and their diameter determines the size of a stitch. Knitting is a more recent invention than weaving, and is far less common.
Embroidery is the process of decorating fabric with ornamental needlework. Unlike tapestries, whose patterns are part of the structure of the weave, embroidery is threaded onto fabrics which are already woven. In general, it is easier (though still laborious) to produce detailed patterns through stitching than through weaving. Embroidery may also incorporate metals and beads in its designs.