The Wool Fibre
Wool is the fibre that makes up the fleece of the domesticated sheep, of which there are many breeds. Some sheep breeds focus on the wool, some on meat, some on a balance between the two. The small Spanish merino sheep produced a fine, soft, short fibre. It was much sought after, but was closely controlled by Spain – for centuries the only ways to acquire a merino sheep were either as a gift from the Spanish king, or by smuggling. The latter method, if you were caught, was punishable by death until 1786.
The British Isles were home to many sheep breeds, producing wool types ranging from coarse wools suitable for tweeds, to long lustrous wools that made smooth worsted fabrics, to short fibers used in making cloths with a raised nap surface, such as flannel or broadcloth. Breeds were crossed to accentuate certain characteristics either of fleece or meat production, or to develop physical qualities to fit a breed to a certain environment. But English sheep were not known for producing very fine fibre - the history of the Australian merino being of great importance here!
The success of efforts to breed sheep with fine long wool, suitable for machine processing, was one factor in the growth of the industrial production of wool. Another was the fact that the Peppin merino was bred to survive and thrive in the Australian hinterlands, encouraging the establishment of huge flocks. This Wanganella (Peppin) wool was less than one micron thicker than Spanish Merino wool, three times longer and just as comfortable when made into clothing.
The Napoleonic Wars not only laid waste to Europe, they put an end to Spanish control of the merino sheep, which were transported to Britain, across continental Europe, and to the United States, Australia, and South Africa. The breed had its ups and downs, but by the late nineteenth century it was a fixture around the world, and many nations, regions, and individuals had bred their own version of the merino sheep: the French Rambouillet, the German Saxony, Australia's Peppin merino, the Vermont (US) merino, etc. Breeds based on the traditional British sheep had also moved around the world, particularly within the British Empire, with new crosses, such as the Corriedale, accommodating these sheep to new surroundings.
Image TBD: Carpet wool sheep and sample.
In addition, vast parts of the world relied (and still rely) on native sheep breeds that produced, by and large, the long, straight, coarse wools that were known in the western/European wool trade as “carpet wools”, as they were best suited to loosely spun yarns and unrefined fabrics.
Colonization spread sheep around the world, and human intervention bred sheep that could survive in regions where they were not native. The wool from these animals became part of a supply chain that fed the textile industries of many nations, and became the uniforms of both their militaries and their diplomats. And while sheep have been adapted to new environments, they have also had lasting impacts on the lands on which they grazed, and the peoples and cultures they replaced.
Characteristics of Wool Fibres
What is it about wool that has made it so valued and so hard to replace?
Crimp: Wool fibers have a natural wave that acts to trap air, and provides natural insulation from temperature extremes. Wave length tends to be shorter in finer wools.
Absorbency: Wool can absorb almost a third of its weight in moisture before it begins to feel damp. Because of this it can keep the wearer comfortable and help regulate body temperature in extremes of heat and cold.
Flame Resistance: Wool fiber contains natural moisture that makes it char and ash (not burn or melt) when exposed to flame. Wool will ignite only when the temperature reaches 570-600 degrees Celsius.
Dyeability: Wool, like silk, is a protein-based fiber, and absorbs most dyes without the need for a mordant (a chemical aid to bond the dye to the fiber). White wool is prized because it is easily dyed. Naturally colored wools are less valuable for industrial manufactures, but prized by artisanal yarn and cloth producers.
Resilience/Elasticity: Wool fiber can be stretched up to 50% of its length when dry and up to 30% of its length when wet without breaking. It will return to its original length when released. This makes it wrinkle resistant and excellent for active usage situations.
Durability/Strength: The wool fiber’s epicuticle layer protects it from wear due to abrasion.
Odour resistance: Wool can absorb as much as 35% of its weight in moisture, and discourages bacterial growth, therefore retarding development of body odours. It also releases odours more completely upon washing than cotton or synthetics.
LINK: http://ag.ansc.purdue.edu/sheep/ansc442/semprojs/2002/wool/characteristics.htm
LINK: U.S. Department of Agriculture. The United States Standards for Grades of Wool. Effective Date Dec. 21, 1968. 21 pages.
LINK: Wool Fact Sheet, and "About Wool". The Woolmark Co. web site.
https://www.woolmark.com/globalassets/02-about-wool/factsheets/gd2405-wool-breathable-_134.pdf
https://www.woolmark.com/about-wool/wool-fibre/
LINK: "Wool Grades and the Sheep that Grow Them." American Wool Council, Div. of American Sheep Industry Association. http://d1cqrq366w3ike.cloudfront.net/http/DOCUMENT/SheepUSA/Wool_Grades_and_the_Sheep_that_Grow_the_Wool_Scan.pdf
LINK: Roy Kettlewell, "Wool 101." American Wool Council Presentation. (90 minutes.) https://www.youtube.com/watch?v=5mv3Z-N_K2I