Thus if a plain cloth with 78 threads per inch of 32’s is taken as the standard, and it is required to make a cloth of equal firmness, with 60’s yarns, the number of threads per inch required would be 106½. In 20’s yarns about 62 threads would be required. In 16’s yarns 55 threads per inch, and so on.
In twills, or other regular weaves, the following rule will give the number of threads per inch required of any count:—
Rule.—As the sum of the ends and intersections in the pattern is to the ends, so is the diameter to the number of threads required.
Example 1.—How many threads per inch are required to make a perfectly balanced “2 and 1” twill cloth, with 24 yarns, warp and weft?
There are 3 ends and 2 intersections in the pattern; therefore
3 ends + 2 intersections = 5;
and as 5 : 3 ends
135