[Illustration: FIG. 18 SCALE AND DESIGN BOARD COMBINED] Fig. 18 represents part of a scale and design board combined. The numbers along the top indicate the threads in the design, and the printer may be supposed to be ready to print the eighth thread. The numbers on the right-hand side represent the wires in the carpet, with which the numbers on the scale board and the scrolls in printing correspond. The design is 216 wires long; and as the number of scrolls the drum will take is 648, the design is repeated three times in one revolution. The scale board is numbered in three columns; and for the first, second, and third repeats of the design, the printer uses the first, second, and third divisions on his scale. To minimise the danger of bad effects from a colour running, the rule is to begin printing with the lightest shade. In this instance, the lightest colour is yellow, represented (heraldically) by spots, and it occurs first at the fourth horizontal line. The printer, therefore, turns the drum by hand, and puts the pawl in tooth number 4. He then puts the mechanism in gear and prints the scroll in the manner described, following on immediately by printing a second scroll at number 5. He then reads further down the eighth vertical line of the design, and sees that the colour recurs at 10, 11, 18, 19, 24, and 25. He therefore puts the pawl in the corresponding teeth of the index consecutively and prints accordingly. When all the yellow squares corresponding to the first column of the scale board have been read, he will take the second column, and print 220, 221, 226, 227, 234, 235, 240, 241 and so on, and then those in the third column. The remaining colours will then follow on in order of their delicacy. When the printing of a drum has been completed, the next process is scraping. The scroll pulley in the act of printing always conveys more pigment on to the yarn than is needed to colour it, a little wall of material being left on each side of the path of the roller. This has to be removed, or it would smudge. This is done by means of small vulcanite tools, bevelled to a blunt edge, from ½ in. to 2 in. wide, the operator being aided by a steel bar fixed across the face of the drum as a guide. Scraping has, however, a further purpose beyond the removal of superfluous colour, and one no less important; for by skilful pressure and rubbing, the colour is caused to penetrate more deeply into the yarn. [Illustration: FIG. 19 A SCRAPER]