334 (#430) ############################################ WOOLLEN AND WORSTED SPINNING made between the "mean” and the "mode" of such curves and of the comparative "contours. contours." It is already obvious that some such mathematical treatment of results of this type may be employed with advantage, but as this type of work still appears to be in its infancy so far as it applies to normal textile examples, refer- ences only to such work are here given. In List XVII on page 336 an interesting series of Flyer, Cap, Ring and Mule Spun Yarns are dealt with under the two types of break, viz. "Fibre-break” and “18 in.-break." B B A A Fig. 100 (IV) Fig. 100 (VI) In addition to the foregoing defects there are many others which arise from time to time—so many, in fact, that one realizes fully why perfect yarns are not spun and perfect pieces woven. This all emphasizes the necessity of bringing into the works the researcher ready to attempt the discovery of any and every defect which arises. With a well-trained researcher, not only may there be a direct value in the results obtained, but a much more valuable indirect result-practice in every section of the works will steadily improve and all the workers will realize, more and more, the interesting problems which are coming up under their very eyes, and consequently may be expected to find in their 334