Twisting the thread directly by hand is similar to twisting the thread by hand, but it is more delicate than twisting the rope. I think the inspiration for twisting comes from twisting rope.
Humans have learned to rub ropes since they entered the fishing and hunting society, which is a prelude to spinning. More than 1000 stone balls were unearthed at Xu Jiayao Cultural Site in Datong, Shanxi, 654.38+ten thousand years ago.
Riprap rope is a net bag made of rope, which can throw stone balls at wild animals when hunting. It can be inferred that people had learned to use ropes at that time.
The rope was originally made of the stem of a whole plant. Later, the splitting and rubbing technology was discovered, that is, splitting the stem bark of a plant into strands, then rubbing many strands together (that is, assembling) and connecting them into a long rope by using the friction between strands.
In order to increase the strength of the rope, I later learned to use a few strands. In 4900 BC, the rope unearthed from Hemudu site in Zhejiang Province was composed of two strands.
Cotton:
Cotton is the seed fiber of Malvaceae, which is native to subtropical zone. The plant is shrubby and can grow to 6 meters high in tropical areas, usually 1 to 2 meters.
The flowers are milky white, turn dark red shortly after flowering, and then wither, leaving a small green capsule called cotton boll. There are cottonseed in the cotton boll, and the fluff on the cottonseed grows from cottonseed hulls and fills the inside of the cotton boll. When the cotton boll matures, it splits, revealing soft fibers. The fiber is white or yellow in white.
It is about 2-4 cm long and contains about 87-90% cellulose, 5-8% water and 4-6% other substances. The countries with the highest cotton production are China, the United States and India.
The growth and development of cotton needs water and nutrients, which are mainly obtained from soil through roots. The required temperature and air are partly obtained from the soil, which needs the mechanical support of the soil to grow. The physical, chemical and biological characteristics of cotton soil greatly restrict the yield and quality of cotton. Soil moisture, nutrients, temperature, air, salt and texture have great influence on cotton growth.