// Workers AI · dad joke modeWhat did Bradford Count say to his date? "You count on me.
The Bradford Count, also known as the Bradford System, English Worsted Yarn Count System or Spinning Count, is a traditional British method of assessing the fineness or fibre diameter of wool.[1]: 729 It is named after the city of Bradford in West Yorkshire.
To measure the fineness of sheep wool fibre before microscopes and lasers were used, English wool handlers in the city of Bradford described wool by estimating (with experienced eyes) how many 560-yard (512 m) hanks of single-strand yarn could be made by a good spinner from a pound (0.454 kg) of "top" (cleaned combed wool with the fibres all parallel). The finer the wool, the greater the number of hanks that could be spun: from a pound of "62s," for example, sixty-two such hanks could be made.[2] Bradford Count values usually range from 28s for coarse wools to 70s for very fine ones.[1]: 730
In the late nineteenth and early twentieth centuries, wool grading still relied on subjective judgement, which led people to look for ways to tie traditional spinning counts to properties that could actually be measured. Some methods compared a sample against reference wool by eye; others used devices that tested resistance, diameter, or how the fibre reflected light. One such device, the "Lichtwaage", was tried at an Icelandic wool station before the First World War.
A table of equivalences with the modern system of measuring fibre diameters in microns was published by the International Wool Secretariat in 1990:[1]: 730
| Bradford Count | Microns |
|---|---|
| 46 | 37 |
| 48 | 35 |
| 50 | 33 |
| 56 | 28 |
| 58 | 25 |
| 60 | 23 |
| 62 | 22 |
| 64 | 21 |
| 66/68 | 20 |
| 70 | 19 |
The Bradford System is widely used among shepherds and breed associations. In 1968, the United States Department of Agriculture issued official standards (for the USA only, not applicable worldwide) which assigned ranges of average fibre diameter and maximum standard deviation to each of the Bradford counts. For example, wool with average fibre diameter in micrometres from 28.60 to 30.09 was to be called "54s".[3]: 63 [4]
References
[edit source]- 1 2 3 Valerie Porter, Lawrence Alderson, Stephen J.G. Hall, D. Phillip Sponenberg (2016). Mason's World Encyclopedia of Livestock Breeds and Breeding (sixth edition). Wallingford: CABI. ISBN 9781780647944.
- ↑ Rodney Kott (1993). Wool Grading. Bozeman, Montana: Montana State University.
- ↑ G.E. Ricketts, R.D. Scoggins, D.L. Thomas, L.H. Thompson, T.R. Carr (revised 1993). Management Guidelines for Efficient Sheep Production. Previously published as: North Central Regional Extension Publication 240, Recommendations for a Sheep Management Program. ISBN 0788182862.
- ↑ Wool Grades and Standards. United States Department of Agriculture: Agricultural Marketing Service. Accessed September 2018.