This installation focuses on four plant fibers—linen, hemp, ramie, and cotton—and illuminates how the Department of Textile Conservation uses innovative analytical equipment, including custom-designed microscope equipment, to identify and examine materials and weave structure, adding greatly to our knowledge of The Met's diverse textile collection.
Close examination of fibers reveals a wealth of information about how a plant is made into fabric. Each factor and condition of a fiber's technological processing—from its planting to its transformation into a textile—affects the aesthetic and functional qualities of the final product, and various combinations of these factors produce a wide range of materials. Linen, hemp, and ramie, for example, are bast fibers, which grow in groups around the plant stalk, under its outer epidermis. These long fibers, between 1 and 2 meters in length, can be spun and/or spliced into yarn. When splicing, the ends of fibers are interlaced and twisted to form a thread. Only long threads can be made into yarn using this process. Cotton is a single-cell fiber that grows in a boll, or pod, attached to a seed. Its short staple fibers, between 3/8 and 2 1/2 inches long, are spun into yarn. Spinning is a process of making yarn from either long or short fibers by steadily pulling and twisting fibers into one continuous element.
Fiber identification contributes greatly to our understanding of where, when, and how a textile was made. In The Met's Textile Conservation lab, the best results are achieved by examining a fiber's longitudinal and cross-sectional morphology under a microscope. See images of plant fibers taken using a microscope (PDF).
Linen fibers are made from flax (Linum usitatissimum), which grows best in rich, wet soil. Although flax probably originated in the Caucasian region between Europe and Asia, linen fibers were skillfully produced in ancient Egypt, northern Europe, and the United States. Linen was one of the most important textile fibers until the Industrial Revolution in the eighteenth century, when cotton production became more efficient and surpassed linen in popularity.
The technological process of producing fine-quality linen fibers involves multiple steps from the cultivation of flax plants to the combing of fibers. Soil richness, climate, and humidity, combined with the high density of plants in a crop and the timing of the harvest are vital early stages. It is also important that the flax plants are separated by categories during harvest. After harvest, the flax plants are immediately sun-dried before being retted (soaked) and scutched (beaten). The drying and retting periods as well as the separation of fibers through repeated combing must be controlled to produce the best linen fibers. The spinning of the threads along with the bleaching of the spun thread and the woven fabric influence the quality of a linen textile.
Hemp (Cannabis indica in Asia and Cannabis sativa in Europe) is primarily used to make textiles and rope. Since the beginning of the twentieth century, increasing industrialization has led to a decrease in hemp production, and the cultivation of this plant is currently regulated in many countries because of its potential illegal use. In Korea, hemp cloth is mainly woven for shrouds and funerary costumes; in Japan, for summer kimonos and textiles for tea ceremonies and shrine offerings; in China and Vietnam, for traditional summer costumes; and in Europe, for clothing and interior furnishings.
Each step of the technological process involved in creating hemp fibers, including planting, harvesting, retting, combing, spinning, and bleaching, affects the quality of the resulting hemp fabric. In Asia, there is a single hemp harvest during June and July. To make hemp threads, long lengths of the fiber layer are collected after the epidermis is scraped off the plant bark. These are finely split and then spliced into yarn, which is twisted to provide additional strength. In Europe, there are two hemp harvests from a single crop, summer hemp (male plants) and autumn hemp (female plants), the latter of which is left to fully mature approximately three weeks longer. The fibers from male plants are thinner and much lighter than those from the female plants. To make hemp threads, the fibers are removed from the plants by retting (soaking) and scutching (beating). The fibers are then combed to separate them according to their quality and to prepare them for spinning.
Ramie (Boehmeria nivea) is native to eastern Asia and grows in subtropical or temperate climates. It is one of the oldest fibers cultivated in Asia and creates finer and more transparent yarns than hemp plants. Much like hemp, the production of ramie fabric declined beginning in the mid-20th century, although it is still used for summer kimonos in Japan and traditional summer hanbok in Korea.
Depending on the climate, ramie stalks can be harvested starting in May or June up to five times a year. Once the bark is collected from the stalks, the outer bark, or epidermis, must be removed immediately from the fiber layer: if the epidermis is left on the fiber layer, it is very difficult to separate later. Next the fiber layer is split into fine pieces, spliced into yarns, and twisted. After ramie fabric is woven, it goes through a bleaching process, which differs by region. For instance, in Korea, ramie fabrics are soaked in water with rice, straw, and ash, and then steamed to remove impurities before being bleached in the sun (ba-re-ki). In Japan, the fabric is usually bleached on snow (yuki-zarashi), while on the islands of Okinawa, in particular, it is bleached in seawater (umi-zarashi).
Cotton (Gossypium) has been an essential staple in textile production worldwide since prehistoric times. Historically, the finest cotton textiles came from India, Egypt, and Turkey, in part because of the expert skills of local hand-spinners, designers, and weavers and their use of long staple fibers. Lesser-known types of cotton, indigenous to Peru, are naturally colored in shades of brown and green. With the invention of the cotton gin by American Eli Whitney in 1793, which mechanized the removal of seeds from the fiber, the speed of production was greatly increased. By the early 19th century, America had become the world's leading producer of cotton.
In 1844, the British scientist and fabric printer John Mercer developed a process known as mercerization, which produces a smoother cotton fiber with great luster, strength, and affinity for dye. Although not widely used until the 1890s, mercerization involves treating cotton with a strong caustic soda solution, which causes the cell wall to first swell and then to shrink and dissolves the cuticle, removing nearly all the exterior structure as well as reducing the twists. Because of the clearly distinguishable ribbon-like twists in cotton, the crisscrossing cellulose strands in the transverse are rarely mentioned or observed, which is an interesting characteristic in microscopy.
Noh Costume (Mizugoromo; detail), 19th century. Japan. Plain-weave, ramie warp, and hemp weft, 43 3/8 x 64 1/2 in. (110.2 x 163.8 cm). The Metropolitan Museum of Art, New York, Purchase, Friends of Asian Art Gifts, 2002 (2002.386)