Guest blog series by: Sophie Mogg
Cotton, we’ve all seen it, heard of it and probably worn clothes made from it too. In today’s installment we’ll be taking a look at Gossypium arboreum, the species of cotton native to India and Pakistan. This particular species was supplied as a single specimen by Carl Linnaeus for his herbarium and was recorded within his own book, Species Plantarum 1753.
Cotton has been cultivated in South Asia from around 3300 BCE. It is a perennial shrub, reaching approximately 2M tall and grown more like an annual due to being harvested every year. The leaves of the cotton plant are lobed, typically having 3-5 lobes and bearing a close resemblance to maple leaves. The seeds are contained within the boll, a small capsule and individual seeds are surrounded by two types of fibres known as staples and linsters. The former is produced into high quality textiles where as the latter produces lower quality textiles. Whilst Gossypium arboreum and its sister plant, Gossypium herbaceum (Africa) only form 2% of the world production of cotton, new varieties of these species are being bread for more desirable traits. One such variety is Gossypium arboreum var. neglecta grown along the Meghna river. This variety, known as “Phuti karpas” is used to make Muslin in Bangladesh as the cotton fibres can be spun to produce threads are more resistant to breaking at higher counts.
The fibres can be separated from the seeds either manually or by use of a machine known as the cotton gin. There are two types of cotton gins, the saw gin for the shorter fibres and roller gin for the longer fibres. The roller gin was invented in India and is used to prevent damage to the longer fibres. Once fibres are separated from the seed they are compressed into lint bales and graded. Carding is the next step, where fibres are pulled so that align parallel to one another and eventually form a sliver which is a rope-like strand of cotton. The slivers are combed to remove impurities before being drawn out into thin strands (roving). The final processing step of cotton is the spinning, where the roving is drawn out and twisted for form yarns and threads for weaving to produce textiles.
Towards the end of the 18th century Manchester had begun to build steam powered mills in order to work with cotton and by 1871 was using approximately 30% of the cotton produced globally. Over 100 cotton mills were built during this time and the industry was supported by The Exchange where over 10,000 cotton merchants would meet in order to sell their wares. The start of the cotton industry across Britain coincided with the Calico act of 1721 being repealed allowing British companies to use cotton in order to make calico, a cheaper and less refined cotton textile, into clothing. Cotton textiles soon became one of the main exports of Britain and is still one of the worlds most used fibres today.
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I’ll soon be travelling to other parts of Asia so I hope you continue to join me. Look for future blogs exploring dyes, medicines and potentially poisons. As always, don’t forget to leave a comment about what you’d like to see from our collection.