This from Isabel Tipton who was in my Coptic Bookbinding class last week. I casually mentioned that linen 25/3 cord thread was a common size for bookbinding but that after 35 years of binding I didn't really know what the numbers referred to. I received this in an email yesterday and felt you all should know. Also I love such beautifully clear expressions of this kind of highly specialized knowledge and vocabulary. One day Pointyhead Press will publish a collection of this kind of writing. Thank you Isabel for getting the ball rolling. To wit:
"We were talking in class about the 24/3 linen thread. 24 lea is 24 x 300 divided by 3 or about 2,000 yards per pound. Isn't knowing that going to make a big difference in your life? Cotton is 640 yards to the pound, same sort of figuring out."
"The standard measure of bulk linen yarn is the lea, which is the number of yards in a pound of linen divided by 300. For example a yarn having a size of 1 lea will give 300 yards per pound. The fine yarns used in handkerchiefs, etc. might be 40 lea, and give 40x300 = 12,000 yards per pound. This is a specific length therefore an indirect measurement of the fineness of the linen, i.e. the number of length units per unit mass. The symbol is NeL.(3) The metric unit, Nm, is more commonly used in continental Europe. This is the number of 1,000 m lengths per kilogram. In China, the English Cotton system unit, NeC, is common. This is the number of 840 yard lengths in a pound.
