The wools of the United States are divided into two groups, territory and domestic. The territory wools, sometimes called •range' or °western,' arc those grown under range con ditions as found in Wyoming, Montana. Idaho, Nevada, Utah, Arizona. New Mexico. Colorado and other Awes where the same conditions prevail. The domestic wools are those grown tinder farming conditions and are often spoken of as °farm," °eastern° or fleece wools.
Sheen in sections producing territory wools territory wools are ext•osed to all {Colds •,', thr for which reason the wool is often harsh and contains more dirt and foreign matter than the domestic wools. Often the fleeces are com posed of very weak fibres or fibres that are weak at some one point in their length. The domestic wools on the other hand are usually strong and are more free from dirt and, therefore. have a smaller shrinkage. They are protected from inclement weather and are given more care and attention than the territory wools.
It has been stated above that there is a large variation in the quality of wools from the different countries. There is a difference in the quality of wools from different breeds of sheep, and indeed there is a variation in the wool on different parts of the same animal. This variation in wools makes it necessary to classify them according to their qualities. Wools are generally separated out according to the grades of the different fleeces, either at the time of shearing or at the wool warehouses. When this work is done at the shearing shed it is sometimes called classing, while at the warehouse it is called grading. The most progressive wool-growing centres of the world class and bale their wool at the time it is shorn, used for the manufacture of worsteds, while the clothing is used in the manufacture of woolens.
Pulled wool or skin wool is wool that us obtained from the pelts of sheep that have been slaughtered or have died from disease or ex posure. It is generally inferior to shorn wool obtained from live sheep. This is due to the methods of obtaining it. The skin is treated chemically or submitted to a special treatment which loosens the roots of the fibres. The wool is then pulled out by hand much as the bristles others ship it to the warehouse where it is graded and baled. Though much advancement has been made in the Western States in the past five years in the manner of handling wool, there is still much room for improvement. There is considerable difference in the terms used in classing and grading wool throughout the world. The terms most widely msed are those of the topmakers' system. They classify wools according to fineness or eflarseness in terms of spinning counts; a spinning count re ferring to the number of hanks of worsted yarn that a pound of a given grade of wool will spin. For example, a lot of wool classed as 60• would spin 60 times 560 yards, or 33,600 yards of worsted yarn. The terms used in the American system, •Boston Terms.' were orig inally based on the proportion of Merino blood a sheep producing the given wool possessed. The pure-blood Merinos, having the finest wool, were used as the standard. These terms are still retained but no longer carry their orig inal significance, as any one of a large number of different breeds might easily produce .1 half
blood wool The terms •staple" or 'combing' and 'cloth ing' arc often added to the grade names to dis tinguish them. Both the staple or combing and the clothing of a given grade are the same fineness, but the combing wools are generally are removed from a hog after scalding. Dur ing the year 1917 there were 40,0130.000 Wends of pulled wool produced in the United States In addition to the pulled wools from the United States there are large wool-pulling establish ments in practically all the large wool-produc ing centres. Mazumet in France is the largest wool-pulling centre in the world.
The following table shows the American grades, together with the corresponding top makers terms: The Wool The wool fibre as has been stated above is the hair-like covering growing on the skin of the sheep. Each fibre is similar to hair in its method of growth. The appearance presented by a cross-section of hair follicle under the microscope is shown is Fig. 2.
The skin of the sheep is composed of four layers, an outer or scarf, which is composed mostly of dead cells; the epidermis, or true skin; a papillary layer filled with minute blood sessels, and finally the dermis or corium. Pro jecting through this skin are innumerable so called hair follicles or sack-like bodies. Each wool fibre is formed in one of these follicles and grows from it. As the fibre is pushed out through the skin it is rather plastic, but on coming to the surface it soon hardens. The stool fibre is composed of three parts. In the centre is the medulla composed of soft globu lar cells. This medulla is well defined in the coarser fibres but in the finer grades of wool is seldom visible even under the most powerful microscope. Next surrounding the medulla are spindle-shaped cells which make up the largest part of the fibre known as corticle, while on the outer part are the horny scale-like cells. These cells surround the outer part of the fibre scales, projecting some what from the body of the fibre and overlapping much like the shingles on a roof. These scales are very important for it is the scales upon the wool fibre that produce what are known as serrations and give the wool fibre its property of felting, a property possessed by no other fibre to such a marked degree. The serrations are most numerous, acute and pointed, in fine •ooled sheep such as Merinos. In Saxony Merino for example as many as 2,800 have been counted in one inch. This surface or epidermal layer of scales gives the wool its lustrous quality. The fibre with smooth flatly lying scales is generally very lustrous. This is well shown in some of our hairy, long-wooled sheep such as the Leicester and Linco!tt. These have fewer serrations, there being about 1,800 spinning, the fibres interlock with their serra tions and the crimp or curliness helps to keep them from untwisting. They also give to cloth made from them a much better felting property, although this property is due only in part to the curliness of the fibres. The serrations or scales, as stated above, play the most important part. There seems to he a definite relation between the curliness and fineness of the wool fibre. The curliness and waviness arc noted points in the judging of wool.