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There has been in recent years an extraordinary development in the scope and application of the knitted fabric which may be traced to a variety of causes. The chief explanation of this growth is to be found in the structure of the knitted fabric itself, the qualities of which have made it pre-eminently suitable for special departments of textiles. In its most elementary form the knitted texture is composed of a series of loops hung in rows one upon the other and constructed from the curvings of a single thread which runs continuously through the fabric. One set of loops is formed on the preceding row and any particular stitch is dependent for its support on neighbouring stitches above, below, and on either side of it; if the thread becomes severed at any point the loops lose contact all round and a considerable opening is incurred. This is its chief defect, but also its outstanding advantage as a texture; it is a defect to have the structure destroyed with the severance of the single ground thread, but it is the mutual interdependence of loops which accounts for its valuable stretch and elasticity. By virtue of this elasticity it becomes eminently suitable for articles of underclothing which have to be worn in close proximity to the cuticle; the fabric is enabled to yield to the slightest movement of any part and thus prevents the wearer becoming uncomfortably conscious of the garment. An inherent yielding quality of the loops causes the article to stretch and adapt itself to minor irregularities of size and shape; if a garment is not exactly to dimensions, it contracts to a smaller or expands to a larger form. This property of stretch must not be unduly taken advantage of to cover up indifferent systems of manufacturing, but within certain limits the property is of great value for certain discrepancies. The knitted fabric is essentially a weft fabric, the thread being inserted crosswise into the texture after the manner of filling so that the entire structure presents a horizontal appearance which is most evident with ground-coloured stripes when the different colours show themselves crosswise. This proves a serious limitation to the scope of the plain knitted texture, for the clothing trades have small use for horizontal effects as compared with vertical coloured stripes. The knitted structure is quite different in property to woven cloth where one has two series of separate threads, one being termed the warp and running longitudinally in the fabric, whilst the other series is named the weft and is intersected with the warp in the process of weaving. The warp threads are pre-arranged to the correct length and in order of pattern on the warp beam whilst the threads of weft are inserted consecutively during the operation of weaving in the loom. This mode of intersecting separate series of yarns at right angles to each other causes the threads to exert a much firmer grip on each other and the resulting fabric is remarkable for its strength and rigidity. It is firm and durable in structure, and possessing comparatively little stretch, it does not yield to the ordinary strains to which it is subjected. It is pre-eminently the fabric to be used for garments of outer wear which have to stand the rough service of every-day life, where a combination of friction, bending and abrasion subject the fabric to a severe test of endurance. In the case of a knitted texture there is a right and a wrong side, or face and back, the face comprising the straight portions of the loops whilst on the back the curved loop portions predominate. Fig. 1 gives a view of a plain knitted fabric showing the right side or the face of the texture where the loops may be distinguished by a characteristic V-shape, these Vs fitting into each other in a vertical direction. This side of the fabric is always worn outermost, as it presents the most even surface whilst it is also the most perfect as all imperfections such as knots, etc., are drawn on to the back of the cloth. Fig. 2 shows the same fabric on the wrong side where it will be noted that the chief feature is a series of interlocking semi-circles which have a distinctly crosswise determination given to them. The appearance on the back is decidedly raw and uninteresting, the straightened V-shaped portions of the loops presenting a much more attractive aspect. On the other hand, most rotary frames work their fabrics with the back in full view of the worker, and in case of analysis it is the wrong side of the fabric which will yield the most definite results to the analyst, for by examination of the curved loops one can discern more easily the character of the pattern and the nature of the ornamentation.

Figs. l and 2

Peculiarities of Knitted Structure.—An examination of the photo-micrograph of the plain knitted fabric (back view) shown in Fig. 3 will demonstrate that the loops are intimately dependent on each other and that the slightest dislocation at any part will at once affect the adjacent area. The knitted fabric is extremely difficult to make absolutely perfect, because each stitch is worked on its own needle distinct from its neighbour, and the slightest irregularity of yarn delivery affects the whole stitch area concerned. If a loop is drawn tighter than the normal at any point, then it is curtailed in size and the adjacent loops have to enlarge themselves to fill out the allotted space. In the woven fabric a missing thread usually influences that portion of the fabric only, but if the main thread of a knitted structure be broken, the entire cloth may be disintegrated with the slightest pull. The interspaces between the loops shown in Fig. 3 are intimately connected with the elastic property, because if the spaces are closed up by tight knitting, the elasticity is considerably reduced, if, on the other hand, the spaces are too large, the fabric loses its equilibrium and a slight pull will cause it to lose its form. An exception to this may be found in the light-weight fabrics so much in demand in recent seasons for wearing in an intermediate position in winter whilst in summer they are worn outermost for lightness. These are purposely knitted flimsy in texture so as to economize material and for summer they are quite elegant and serviceable when manufactured in attractive colourings. For winter use they are possessed of a heat-retaining property which would not be expected from their bulk, but to attain the best results they must be worn under a fabric of stronger and more durable construction. The theory of these surprising results is that free interspaces act as so many air chambers which contribute to non-conductivity of heat by the garment. Face veils are usually very flimsy structures, but on account of the "still layer" of air retained in the vicinity of the face the heat is effectively retained just as if a fabric of much heavier construction were employed.

Fig. 3

This property should be fully investigated in a scientific manner in the light of increased cost of raw materials which has now become vital to the manufacturer and his public. In many circles weight of cloth is synonymous with warmth, but experience has shown that this is not the case and that the warmest garments are not always the heaviest. The latest converts to the light-weight article are the clothing departments of the services where, as a result of war experience they have altered many specifications to include fabrics much lighter in weight; formerly no gauge or sett could be too coarse and thick for their requirements, but now the products of all gauges in the equipment of the hosiery manufacturer are utilized. Now the matter is being brought more fully to the notice of the manufacturer on account of the great rise in the price of raw materials when it is essential to extract the utmost farthing of utility from every ounce of material. If we can more fully requisition the services of the "still layer of air" in this regard it will prove an inexpensive medium of clothing.

Knitting Trade Definition.—The meaning of the term hosiery has undergone a great expansion during the past decade and its present meaning is an eloquent testimony to the enormous growth which the trade has recently experienced. Originally the term had reference chiefly to articles of footwear, it was in this regard that the utility of the knitted stitch was first recognized. The feet form a delicately susceptible part of our anatomy and require special care in fabric selection. In walking the muscles and tendons of the foot are in constant action and it is of vital importance to the comfort of the individual that the footwear should be worked in the most suitable fabric. To have footwear in the woven texture is unthinkable if from no other reason than the seams which would be necessary, and to have one of these located at the heel or along the sole of the foot would render the wearer unable to walk in a very short period. There is further the matter of perspiration which occurs so profusely at the pedal extremities, and the knitted texture above all others is adapted to that intimate sort of interaction between skin and fabric which is required for the absorption of perspiration. It laps it up and gives it back again gradually in the form of vapour. In a fabric of less absorbent qualities the article would soon fill with moisture and giving rise to wetness cause considerable discomfort to the wearer. The term hosiery has greatly outgrown its original significance as applied to footwear only and now embraces underwear, articles used for intermediate garments and an increasing range of garments suited for outer wear. There are now very few departments of clothing into which the knitted texture has not penetrated. For outer garments it is not always advisable to employ the knitted texture in its entirety because it obviously does not possess all the properties needed, but great progress has been made in the direction of giving greater stability by a judicious use of the more rigid woven texture at given points. For example, in the knitted vest trade the garment edges are often bound with tapes of woven stuff, whilst the linings are invariably made from these materials. Incidentally the colour of these reinforcing materials is so chosen as to harmonize with the ground so that the whole garment is enhanced in general appearance. Similarly it is found that the plain knitted loop is neither heavy nor close enough to give adequate comfort for an outer garment, which deficiency has been attended to by the hosiery machine builders who have made such improvements on the machines as will enable much more yarn to be inserted in a given space. This increases the sett of the loops and the weight and rigidity of texture, so that fabrics may now be obtained which are almost equal to the woven fabric in resistant properties. Such modifications of fabric structure usually result in a pattern with a prevailing one-sided effect, the wrong side being deficient in appearance and style. The ordinary plain knitted stitch per se has little scope for ornamentation unless special machines are employed and where embellishment is required on a plain garment it often takes the form of added pieces of crochet.

Figs. 4, 5, 6 and 7

Crochet Work.—This is particularly useful in the trade for children's garments where many factories employ crochet workers who ornament the edges by crochet patterns worked in the same yarn. For the very tiny articles of this class it is often found uneconomical to employ machines, and in certain districts large numbers of such garments are produced by the hand crochet workers where the greatest freedom of loop selection is possible. The operation of hand crochet is illustrated in Figs. 6 and 7 where the hook is marked H; in Fig. 6 the hook with loop A upon it is about to grip a portion of the new yarn B, and in Fig. 7 this has been drawn through the old loop to add a new one to the chain. In this way one can have on a garment effects which could only be produced by changing to several types of machines, and when articles are small this changing is not economically sound. There are still a considerable number of these crochet workers in various parts of the United Kingdom notably in rural districts of Ireland and in various districts of Scotland and England. Many large firms have a number of such hands attached as an outside staff and they are useful for scrutinizing fashion publications and producing stitches with hand pins which may with good results be adapted to machine-made goods. They have subsidiary departments where customers are supplied with articles of distinctly novel character and for which they are prepared to pay enhanced prices. The freest of all mediums of ornamentation in this class is undoubtedly the crochet, and articles are often ornamented with distinctly elegant results by the use of the crochet hook. By this means yarn same as the ground is employed so as to render it homogeneous and elegance of pattern is due to the fact that the worker can select any point of the fabric for a new move of the pattern. We may have one style being worked at this point and an inch farther up a distinctly different pattern can be evolved. In many rural districts the workers have attained remarkable skill in pattern origination due to their life-long devotion to the handicraft; from the art view-point it is hoped that they will continue to secure such an outlet for their work as will reward their skill and devotion. It is admitted that such products may not hold their own in fierce competition of the open market, but "Man does not live by bread alone," and it is hoped that public taste for such artistic productions may be maintained and developed in contrast to the strictly utilitarian; the aesthetic sense is one which the British as a nation sadly lack.