Wool Sorting

Fleece wool as it comes to the mill is rolled up in bundles and must

be sorted. This process consists in sorting and classifying the fibers

of the fleece. Not only do the various species of sheep furnish widely

different qualities of wool, but different qualities are obtained from

the same animal, according to the part of the body from which the wool

is taken. This variation in some instances is very marked, and

someti es is greater than that which separates the wools of the

different breeds of sheep. Hence the sorting and classing of wool

become necessary for the production of good, sound yarn of even

quality.



An attempt to utilize the fleece as a whole would result in the

spinning of uneven, faulty, and unsatisfactory yarns. As many as

twelve or fourteen sorts may be obtained from one fleece (by very fine

sorting), but generally not more than five or seven are made. The

following table shows the relative qualities of wools from the various

parts of a Merino sheep:



1 and 2. Head (top and sides): The wools grown on these parts are

remarkable for length of staple, softness, and uniformity of

character. They are usually the choicest wools in the fleece.



3. Upper part of the back: This also is a wool of good, sound

quality, resembling in staples Nos. 1 and 2, but not as soft or as

fine of fiber.



4. Loin and back: The staple here is comparatively short, not as

fine, but generally of unvarying character, sometimes rather tender.






5. Upper parts of legs: This wool is medium in length but coarse of

fiber, and has a tendency to hang in loose, open locks. It is

generally sound, but likely to contain vegetable matter.



6. Upper portion of the neck: The staple clipped from this part of

the neck is of an inferior quality, frequently faulty and irregular in

growth, and contains twigs, thorns, etc.



7. Central part of the neck: This wool is similar to No. 6 but

rather tender in staple.



8. Belly: This wool is from under the sheep, between the fore and

hind legs. It is short and dirty, poor in quality, and generally

tender.



9. Root of tail: In this wool the fibers are coarse, short, and

glossy.



10. Lower parts of the legs: This wool is generally dirty and

greasy, the staple having no wave and lacking fineness. It is

generally burry and contains much vegetable matter.



11. Front of Head; 12. Throat; 13. Chest: The wools from these

parts are sometimes classed together, all having the same

characteristics. The fiber is stiff, straight, coarse, and covered

with fodder.



14. Shins: This is another short, thick, straight wool of glossy

fiber, commonly known as shanks.



=Classing.= Classing is a grading of the fleeces, and is usually, but

not always, a process preliminary to sorting. It is an important part

of sorting, and when well done greatly facilitates the making of good,

uniform matchings.



=Grades of Wool.= In the grading of wool no set standard of quality

exists. The same classification may be applied in different years, or

in different localities, to qualities of wool showing much variation,

the best grade obtainable usually setting the standard for the lower

grades. The highest quality of wool in the United States is found on

full-blooded Merino sheep.



=Merino Wool.= The Merino sheep was bred for wool and not mutton. The

fleece of this breed is fine, strong, elastic, and of good color; it

also possesses a high felting power. Though naturally short, it is now

grown to good length and the fleece is dense. The Merino sheep is a

native of Spain, and Spain was for a long period the chief country of

its production. It was also in past centuries extensively bred in

England and English wool owes much to the Merino for the improvement

it has effected in the fleeces of other breeds of English sheep. It

was also introduced into Saxony and was highly bred there, and Saxony

soon came to surpass Spanish wool in fineness, softness, and felting

properties. The Merino was introduced into the United States at the

beginning of the nineteenth century. By 1810, 5,000 Merino sheep had

been imported and these 5,000 sheep formed the basis of most of the

fine wool-producing flocks of our country to-day.



The terms half blood, three-eighths blood, and quarter blood refer to

the full-blooded Merino standard. As the scale descends the wool

becomes coarser, the wool of a quarter blood usually being a

comparatively coarse fiber. The general classifications of fine,

medium, coarse, and low, refer to the relative fineness of Merino

combing wools. These distinctions naturally overlap according to the

opinion of the parties in transactions. Picklock XXX and XX represent

the highest grades of clothing wool, the grade next lower being X, and

then Nos. 1 and 2. These again are used in connection with the

locality from which the wool is grown, as Ohio XX, Michigan X, New

York No. 1, etc.



=Difference Between Lamb's and Sheep's Wool.= One of the first points

to be understood in wool sorting is the difference between the wool of

lambs and one-year-old sheep, and that of sheep two or more years old.

Lamb's wool is naturally pointed at the end, because it has never been

clipped. It is termed hog or hoggett wool, and is more valuable when

longer, of about fourteen months' growth. It is finer in quality and

possesses more waviness, which is a help in the process of spinning.



The wool of sheep two or more years old is known as wether. The ends

of the fiber from such sheep are thick and blunted, on account of

having been previously cut. It is necessary to be able to tell at once

a hog fleece from a wether, and this can be done in two ways: by

examining the ends of the fiber to see if they are pointed; or by

pulling a staple out of the fleece. If it is wether, the staple will

come out clean, without interfering to any extent with those around

it; but if hog, some of the fibers will adhere to the one that is

being pulled. Hog wool is generally more full of dirt, moss, straw,

and other vegetable matter.



=Dead Wool= is wool obtained from the pelts of sheep that have died.



=Pulled Wool.= Pulled wool is wool from the pelts[10] as they come

from the slaughter-houses of large packing plants. These pelts are

thrown into vats of water and left to soak for twenty-four hours to

loosen the dirt which has become matted into the wool. From these

vats the pelts are taken to scrubbing machines from which the wool

issues perfectly clean and white. The pelts are next freed from any

particles of flesh or fat which may have adhered to them, and are then

taken to the "painting" room. Here they are laid flesh side up and

carefully painted with a preparation for loosening the roots of the

wool. This preparation is allowed to remain on the pelts for

twenty-four hours, when it is cleaned off and the pelts taken to the

"pulling" room. Each wool puller stands before a small wooden

framework over which the pelt is thrown, and the wool, being all

thoroughly loosened by the "paint" preparation, is easily and quickly

pulled out by the handful. As it is pulled it is thrown into barrels

conveniently arranged according to grade and length.



When a barrel is filled, it is transferred to a large room across

which are several rows of wire netting, raised about three feet from

the floor. Each sheet of netting is about six feet wide. Here the wool

is piled on the netting to a depth of several inches and hot air is

forced underneath it by means of a blower. Meanwhile it is worked over

by men with rakes, and soon dries. When thoroughly dry, it is raked up

and taken to the storeroom, where it is dumped into bins. Here it

usually remains open for inspection and sampling till it is sold, when

it is bagged. The bags of wool ultimately find their way to the woolen

mill or sampling house. Sometimes the fleece will retain its fleece

form, but usually it breaks up. The wool contains lime and has to be

specially treated by a scouring process to prevent lime from

absorbing the cleansing substances used for scouring the wool.



=Delaine Wool= is a variety of fine, long combing wool.



=Cotty Wool=, or cotts, is wool from sheep that have been exposed to

severe weather and lack of nourishment, and for these reasons have

failed to throw off the yolk necessary to feed the wool. As a result

it becomes matted or felted together, and is hard and brittle and

almost worthless.



=Wool Sorter.= The sorter begins by placing the fleece upon his board

or table, always arranging it so that he faces the north, as this

gives the most constant light and no glare of the sun. The fleece thus

spread out shows a definite dividing line through the center. The

sorter parts the two halves and proceeds to analyze their different

qualities. The number of sorts is determined by the requirements of

the manufacturer who, in purchasing his wool, buys those grades that

will produce the greatest bulk of the qualities for present use, and

that leave in stock the smallest number of sorts and least weight for

which he has no immediate use. The sorter then removes all extraneous

matter adhering to the fleece, such as straw, twigs, and seeds, and

cuts off the hard lumps of earth, tar, or paint, which, if not removed

at this time, will dissolve in the scouring process and stain the

wool. With these preliminaries finished, he proceeds to cast out the

locks, according to quality, into baskets or skeps provided for that

purpose. After skirting or taking off the outside edges of the fleece,

usually known as brokes, and the legs and tail, known as breech, he

separates the other portions from the better qualities.




DEGREASING PLANT]



Picklock, prime, choice, super, head, downrights, seconds, breech,

etc., are some of the terms used. Picklock comprises the choicest

qualities; prime is similar to picklock, but slightly inferior; choice

is true staple, but not as fine in fiber; super is similar to choice,

but as a rule not as valuable; head includes the inferior sorts from

this part of the sheep; downrights come from the lower parts of the

sides; seconds consist of the best wool clipped from the throat and

breast; breech, the short, coarse fibers obtained from the skirting

and edgings of the fleece.



In the worsted trade different names are used. The terms generally

adopted are: blue, from the neck; fine, from the shoulders; neat, from

the middle of the sides and back; brown-drawings, from the haunches;

breech, from the tail and hind legs; cowtail, when the breech is very

strong; brokes, from the lower part of the front legs and belly, which

are classed as super, middle, and common.



Fine, short wools are sorted according to the number of counts of yarn

they are expected to spin, as 48's, 60's, 70's, and so on. Thus we see

there are different methods of indicating qualities in different

districts, and also of indicating differences of qualities between the

woolen and worsted branches of the trade.



It may be noted that the quality of the wool varies in the same way as

the quality of the flesh. The shoulder is finest in grain and most

delicate, so the wool is finer in fiber. There is more wear and tear

for the sheep at its haunches than at its shoulders, hence the wool is

longer and stronger; about the neck the wool is short, to prevent the

sheep from being weighted down while eating, etc.; the wool on the

back becomes rough and thin, being most exposed to the rain. From the

foregoing it will be readily seen that there is necessity for careful

sorting, in order to insure obtaining an even running yarn, and

subsequently a uniform quality of fabrics.



=Wool Washing.= Fleece wool as it comes into the market is either in

the "grease," that is, unwashed and with all the dirt which gathers on

the surface of the greasy wool; or it is received as washed wool, the

washing being done as a preliminary step to the sheep shearing. Wool,

unlike cotton, cannot be worked into yarn without being thoroughly

cleansed of its impurities. These impurities consist of greasy and

sweaty secretions, of the nature of a lubricant to the fiber. Combined

with dirt, sand, etc., which adhere to the wool, these secretions form

an encrusting compound, known as yolk, which acts as a natural

preservative to the wool, keeping it soft and supple. This compound,

with other extraneous matter, must be removed before the wool is in a

workable condition. The amount of yolk varies, the greatest amount

being found in fine, short wools from the warm climates. In

long-staple wool the amount of yolk is comparatively small.






Various methods of removing these impurities have been tried; one is

the use of absorbent substances, such as fossil meal, alumina, etc.,

to withdraw the greasy matter, so that the remaining impurities can be

easily removed by washing. In other methods, naphtha or similar

solvent liquids are used to dissolve the wool fats. This is followed

by washing in tepid water to dissolve the potash salts, leaving the

dirt to fall away when the other substances are no longer present. To

work this method with safety requires a costly and intricate plant

with skilled supervision. The method which is practically in universal

use is washing the wool in alkaline solutions, properties of which

combine with and reduce the impurities to a lathery emulsion which is

easily washed off from the wool.



Great stress is laid upon the necessity of care in the washing

process, as the luster may be destroyed and a brownish-yellow tint

given to the wool, the spinning properties very seriously injured, the

softness destroyed, or the fiber dissolved. Some wools are easy to

wash, requiring little soap and a reasonable temperature; other wools

are cleansed with great difficulty. A note, therefore, should be made

of any particular brand or class of wool requiring special attention,

to serve as a guide in the treatment of future lots. The danger lies

in using unsuitable agents,--hard water, excessive temperatures,

strong reagents, etc.



Caustic alkalies have a most destructive effect on wool as they eat

into it and destroy its vitality. Carbonate alkalies are less severe.

Whatever cleansing substances are used, it is essential that they

should be free from anything that is likely to injure the wool--that

they remove the impurities and still preserve all the qualities in the

wool. If the washing is properly performed the alkaline portion of the

yolk is removed, leaving only the colorless animal oil in the fiber.

If the work is not thoroughly done the wool passes as "unmerchantable

washed." "Tub washed" is the term applied to fleeces which are broken

up and washed more or less by hand. Scoured wool is tub washed with

warm water and soap, and then thoroughly rinsed in cold water until

nothing remains but the clean fiber.






An improved method of washing wool by hand is to have a series of

tanks with pressing rollers attached to each tank: the wool is

agitated by means of forks, and then passed to the pressing rollers

and into each tank in succession. The tanks are usually five in

number, and so arranged that the liquor can be run from the upper to

the lower tank. Upon leaving the pressing rollers the excess of water

is driven off in a hydro extractor[11] and the wool is beaten into a

light, fluffy condition by means of a wooden fan or beater.



=Wool Drying.= The process of drying wool is not intended to be

carried to such an extent that the wool will be in an absolutely dry

state, for in such a condition it would be lusterless, brittle, and

discolored. It is the nature of wool to retain a certain amount of

moisture since it is hygroscopic, and to remove it entirely would

result in partial disintegration of the fibers. Buyers and sellers

have a recognized standard of moisture, 16 per cent. If, on the other

hand, it is left too wet, the fibers will not stand the pulling strain

in the succeeding operations, and if not broken, they are so unduly

stretched that they have lost their elasticity.



The theory which underlies the drying process is that dry air is

capable of absorbing moisture, hence by circulating currents of dry

air in and around wet wool, the absorbing power of the air draws off

the moisture. For continuous drying free circulation is a necessity,

as otherwise the air would soon become saturated and incapable of

taking up more moisture. Warming the air increases its capacity to

absorb moisture; thus a higher temperature is capable of drying the

wool much quicker than the same volume of air would at a low

temperature. A free circulation of air at 75 to 100 degrees F., evenly

distributed, and with ample provision for the escape of the saturated

air, is essential for good work.



=Oiling.= After being scoured wool generally has to be oiled before it

is ready for the processes of spinning, blending, etc. As delivered

from the drying apparatus, the wool is bright and clean, but somewhat

harsh and wiry to the touch, owing to the removal of the yolk which is

its natural lubricant. To render it soft and elastic, and to improve

its spinning qualities, the fiber is sprinkled with lard oil or olive

oil. As the oil is a costly item, it is of consequence that it be

equally distributed and used economically. To attain this end various

forms of oiling apparatus have been invented, which sprinkle the oil

in a fine spray over the wool, which is carried under the sprinkler by

an endless cloth.



=Burring and Carbonizing.= After wool has been washed and scoured it

frequently happens that it cannot be advanced to the succeeding

operations of manufacture because it is mixed with burs, seeds,

leaves, slivers, etc., which are picked up by the sheep in the

pasture. These vegetable impurities injure the spinning qualities of

the stock, for if a bur or other foreign substance becomes fastened in

the strand of yarn while it is being spun, it either causes the thread

to break or renders it bunchy and uneven. For removing burs, etc.,

from the wool two methods are pursued: the one purely mechanical, the

other chemical, and known respectively as burring and carbonizing.



=Bur Picker.= For the mechanical removing of burs a machine called the

bur picker is employed. In this machine the wool is first spread out

into a thin lap or sheet; then light wooden blades, rotating rapidly,

beat upon every part of the sheet and break the burs into pieces. The

pieces fall down into the dust box or upon a grating beneath the

machine, and are ejected together with a good deal of the wool

adhering to them. Often the machine fails to beat out fine pieces and

these are scattered through the stock.



=Process of Carbonizing.= For the complete removal of all foreign

vegetable substances from wool the most effective process is

carbonizing, in which the burs, etc., are burned out by means of acid

and a high degree of heat. The method of procedure is as follows: The

wool to be treated is immersed in a solution of sulphuric or

hydrochloric acid for about twelve hours, the acid bath being placed

in cement cisterns or in large lead-lined tubs and not made strong

enough to injure the fiber of the wool. During the immersion the stock

is frequently stirred. Next, the wool is dried and then placed in an

enclosed chamber and subjected to a high temperature (75 degrees C.).

The result of this process is that all the vegetable matter contained

in the wool is "carbonized" or burned to a crisp, and on being

slightly beaten or shaken readily turns to dust. This dust is removed

from the wool by various simple processes. The carbonizing process was

first introduced in 1875, though it made but slight headway against

the old burring method until after 1880.



=Blending.= Pure wool of but one quality is not often used in the

production of woven fabrics, so, before the raw material is ready for

spinning into yarn, or for other processes by which it is worked into

useful forms, it is blended. Wools are blended for many reasons (among

which cheapness figures prominently), the added materials consisting

usually of shoddy, mungo, or extract fibers. Ordinarily, however,

blending has for its object the securing of a desired quality or

weight of cloth. The question of color, as well as quality, also

determines blending operations, natural colored wools being frequently

intermixed to obtain particular shades for dress goods, tweeds,

knitting yarns, etc. Stock dyed wools are also blended for the

production of mixed colors, as browns, grays, Oxfords, etc. There is

practically no limit to the variety of shades and tints obtainable by

mixing two or more colors of wool together. The various quantities of

wool to be blended are spread out in due proportion in the form of

thin layers, one on top of the other, and then passed through a

machine called the teaser. The teaser consists of a combination of

large and small rollers, thickly studded with small pins, which open

the wool, pull it apart, and thoroughly intermix it. A blast of air

constantly plays upon the wool in the teaser and aids the spikes and

pins in opening out the fibers. The material is subjected to this

operation several times and is finally delivered in a soft, fleecy

condition, ready to be spun into yarn.