In the scutcher it is the most common practice to take four laps from the opener and to place them in a specially constructed creel and resting on a travelling "lattice" or apron. By this they are slowly unwound and the four sheets are laid one upon another and passed in one combined sheet, through feed rollers, to a two or three bladed beater, exactly like the second one described when treating upon the double opener. Also, exactly in the same manner, a lap is formed ready for the immediately succeeding process of carding. In the scutcher the doubling of four laps together tends to produce a sheet of cotton more uniform in thickness and weight than that from the opener. This object of equality of lap is also invariably aided by what are termed Automatic Feed Regulators, which regulate the weight of cotton given to the beater to something like a continuous uniformity. The action is clearly seen in the illustration.
Carding.—By many persons this is deemed to be the most important operation in cotton spinning. Its several duties may be stated as follows:—
1. The removal of a large proportion of any impurities, such as broken leaf, seed and shell, that may have escaped the previous processes. It may usually be deemed to be the final process of cleansing.
2. To open out and disentangle the clusters of fibres into even greater individualisation than existed when first picked, and to leave them in such condition that the subsequent operations can easily draw them out, and reduce them to parallel order.
3. The extraction of a good proportion of the short, broken and unripe fibres, present more or less in all cottons grown, and practically worthless from a manufacturing point of view.
4. The reduction of the heavy sheet or lap of cotton from the scutcher, into a comparatively light and thin sliver. Ordinarily, one yard of the lap put up behind the card weighs more than 100 times as heavy as the sliver delivered at the front of the card.
There are several varieties of Carding Engine, but in each case nearly all the essential features are practically the same in one card as in another. At the present time, the type of Carding Engine which has practically superseded all others is denominated the "Revolving Flat Card." This Card originated with Mr. Evan Leigh, of Manchester, and after being in close competition with several other types has almost driven them out of the market. Of course it has been considerably improved by later inventors, and various machine makers have their own technical peculiarities.
In the illustration seen in [Fig. 15] there is conveyed an excellent idea of the appearance of the heavy lap of cotton as it is placed behind the Carding Engine, and of the manner in which the same cotton appears as a "sliver" or soft strand of cotton as it issues from the front of the same machine, and enters the cylindrical can into which it is passed, and coiled into compact layers, suitable for withdrawal at the immediately succeeding process.
