233 (#305) ############################################ CHAPTER IX WORSTED SPINNING PRINCIPLES AND PRACTICE THE worsted drawer starts with the "top," and in order that he may produce a level roving knows that he must start with a well-combed “top” free from the blemishes of broken and short fibres, neps, bits of vegetable matter and any irregularities. Similarly the worsted spinner starts with the “roving," and in order that he may produce a level, sound yarn knows that he must start with a level roving capable of being extended to the count of yarn to which he desires to spin without showing "twittiness,” irregular twisting, or any other of the defects which may be associated with the spun thread. Just as the worsted drawer will, if possible, keep clear of drawing newly combed tops (called “hot” tops), so possibly may the worsted spinner keep clear of newly drawn rovings.* The probable reason for this, viewed in the light of recent researches, is that while the wool fibre is very stable—much more so than has been realized until recently-all drafting pro- cesses do tend very slightly to elongate it and to take out the natural curl of the fibre and thus make it unstable, as it were alive." In addition to this arti- ficially developed physical instability there is the * It is interesting to note that this remark applies only to oil- combed and drawn, twisted slivers treated on the English system; the French drawer, dealing with a dry, untwisted sliver, does not hesitate to spin straight from the roving frame. 233
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