In blends of diffierent qualities of wools, or of wools and other fibres, one general principle should always guide the proceedings. This should be to spread out a thin layer of one quality on a clean floor over as wide an area as convenience will permit, upon which all the successive layers should be placed equally thinly, and in proper rotation. The batch should he well beaten down with sticks, which .will help to blend the materials, and keep the bulk within reasonable compass. When used, the material should be. always taken from the sides : drawn dowu vertically from top to bottom by means of a short-pronged rake. This will secure a thorough intermixture of the mass. To take from the top, it will be obvious would simply be to separate the materials again.
Wool and Silk Waste.—In laying down a blend of wool and silk waste, it is important to see that the sIlk is cleared from the natural gum, as otherwise it will not easily intermix, and in after processes could with difficulty be retained. Should it afterwards be subjeoted to warmth and moisture, it is also liable to have its gum partially dissolved, which would cause it to adhere to other portions, and to clog the machinery in an inconvenient manner. The next point of irnportance is that the silk waste must he of the colour intended for the ground of the fabric, and not that of the relieving mixtures. Should it be intended to produce a gray mixture of say 75 per cent. black and 25 per cent. white, the silk waste must form a portion of the black. The wool before the admixture takes place should al ways be thoroughly well scoured. The silk waste should be reduced in the fibres as nearly as possible to the length of staple of the wool with which it has to be mixed. The fineness should also approximate as closely as can be attained. The silk portion of the blend being extremely light, it is requisite to have all parts of the carding machinery—cylinders, workers, doffers, and " fancy "—very accurately adjusted, and the clothing smooth and sharp. The doffers should not exceed about 4 rev. a minute, and the " fancy " ought only barely to exceed the rate of tho cylioder, so as to work with as little draught as possible, in order to prevent the generation of electricity. Oleine is the best lubricant for this blend, but care must be taken to have it free from acid.
Wool and Cotton.—Blends of wool and cotton are usually for hosiery purposes. In this class of mixtures, the Belgian manufacturers have achieved considerable eminence. With their system, they have successfully mixed all proportions of wool and cotton, reducing the former element until it has become conspicuous mainly by its absence. In each case they have produced useful yarns—
at a price with which other spinners and manufacturers have found it difficult to oompete. The poorer qualities of course are devoted to the production of low grades of yarns. These have usually been known as " Vigogne " yarns, so called from a Brazilian animal whose fleece partakes of the characters of those of the sheep and the goat.
A high quality of this yarn would be composed of half wool and half cotton. Both materials should be good and sound in staple. The wool ought to be fine merino, and the cotton of long staple and very clean. The wool should be thoroughly cleansed from dust and foreig-n substances, well scoured, carefully dried, willowed, and oiled. The carding process requires to he carefully performed, the ordinary breaker-card being usually selected. All the parts should be accura,,tely adjusted, the workers put on slow speed, and the clothing perfectly smooth and possessing a good working point, so that the wool on being put through shall be delivered as straight as possible. It should be made into a lap in this process, The cotton ia first put through the opener, and made into a lap. For good work, it is then carded to take out all short or defective fibre, nem motes, S:e., in order to secure a elear yarn. Where this ia not essential, the carding may be dispeneed with. After carding, the slivers are again put through the opener to faeilitate admixture with the wool. The proportione of each axe next weighed out, blended together, and again put through the teazer once or twice in order to secure thorough admixture. The slivers are then ready to go through the woollen card and condenser. The result, if the operations are properly performed, will be a clean, level, and thoroughly uniform yarn.
Where the highest resulta are not wanted, a simpler method is often adopted, The proportions being decided on, and weighed out, the wool is first toned, then oiled, then teazed again. The cotton is next put through the opener, after which the material° are carefully mixed, each layer being spread out very thioly one over the other until the blend is completed, when the mixed material le taken from the side, and again passed once or twice through the teazer, care being taken each time to further blend the material, when It is brought from the front to the back of the machine, by turning the outside of the mass to or upon the middle, there being a tendency (owing to difference of specific gravity of the two fibres) to separate. The cotton must in no case be oiled, as it will take from the wool all the oil it will require.