Shetland Tweed research
Shetland Tweed has its origins in the cloths that have been woven in the islands for thousands of years.
In the Shetland Museum and Archive Store is a wonderful example of a skirt and jacket made from Shetland Tweed. Dating to the early part of the 20th Century, the pieces are soft, possibly due to being carefully hand-washed and cared for, and they match an 18th Century description of "glittering appearance as though varnished". This description comes from a 1791 abstract attached to a report commissioned by the Society for the Improvement of British Wool in Edinburgh, entitled "Report of the state of sheep-farming along the eastern coast of Scotland, and the interior parts of the Highlands. By Andrew Ker”. This report (pictured. An Italian translation dating from 1793 has been purchased and added to this research documentation), now in the British Library (referenced here) was aimed at protecting the wool industry in the British Isles. Attached to it is a separate article written by John Tulloch, “a native of Shetland” about the sheep of the islands in which an appeal is made for the protection of the native sheep due to the quality of the fleece, that quality coming from two types of these fine wooled Shetland animals. One of the types produced, according to Tulloch, short, close fibres fit for carding while the other produced longer fires, useful for combing. The former is “close, curled or waved…” and presents the lustrous sheen that John Tulloch wrote about. The latter was noted as being “often as soft but seldom as fine… more open in the locks and straighter in the pile”. These differences, it is to be presumed, would produce both combed and carded yarns, one for worsted spinning and the other for woollen spun yarns.
Carding and combing / woollen and worsted
The difference between carded and combed yarns lies in their preparation. Carding is a method that leaves some of the woolen fibres bent prior to spinning while the majority of them lie parallel to each other. Generally speaking, carding is a process that pulls fibres through teeth, either on a hand carding pair of paddles or, in industrial production, drums. Repeated carding produces a rolag that is then twisted to produce a woollen-spun yarn.
Combed yarns by contrast are, as the name suggests, combed and this has two effects: removal of the shorter fibres and no bend in those that are left. Combing produces a less airy yarn when spun, but, because the fibres all lie parallel, it is generally stronger. This yarn is a worsted-spun type.
Worsted is the kind of yarn most often used in weaving because of its strength, except in the case of Scottish tweed, which, to be authentic, must be created by the woollen-spun process, known as "The Scotch system".
John Tulloch’s report states that the intermixing of the two qualities of wool, those fit for carding and those useful for combing, give the varieties of colour in the finished yarn as well as different tactile qualities. It is apparent from this account that the sheep from Shetland were noted for these characteristics and it is still the case that the native sheep are known by the names for their markings and colouration: katmoget, shaela, etc.
While John Tulloch’s appendix to an important report may have come about for a variety of reasons, amongst them the influence of absentee landowners who wanted to increase the numbers of sheep on their holdings, it is important to the story of Shetland Tweed to note that it exists. Shetland at the end of the 18th Century was known for its wool production, and for the lustrous softness of the resulting yarns (Italics mine); qualities have been valued for centuries in the native sheep breed.