109 (#163) ############################################ WOOLLEN YARN SPINNING forgotten that the woollen mule is specially designed for short-fibre spinning—long fibres cannot be drafted on the spindle-draft principle, the twist at once binding such into undraftable slivers; and that short fibres-even on the spindle-draft principle-cannot be given a draft of more than two, or, in very extreme cases, say three. The great bulk of woollen yarn is spun with a draft of 11 to 2, while quite a considerable quantity is spun with a very slight gain of the carriage on the delivery rollers, the yarn thus produced being really a twisted condensed sliver rather than a spun woollen thread. It should here be stated that the soundest and best woollen thread will be produced by condensing to a thick count and drafting (spinning) to the count re- quired. If the drafting (spinning) cannot be effected at one operation, it should be effected by roving first and then spinning. The following are possible methods of producing a 36 skeins (36 yards to the dram) woollen yarn :- Condensed sliver Roved to Spun to i intro no I. 2 3 4 5 6. 34 skeins 24 skeins 18 skeins 12 skeins 24 skeins 25 skeins 18 skeins 12 skeins (draft 11) 30 skeins (draft 1}) 30 skeins (draft 1}) 24 skeins (draft 2) 24 skeins (draft 1117) 36 skeins (draft 1t) 36 skeins (draft 2) 36 skeins (draft 3) 36 skeins (draft 1}) 36 skeins (draft 15) 36 skeins (draft it) 36 skeins (draft 11) 36 skeins 8 Of the above (I) is not really a spun thread; (5) and (6) are worth comparing from a mathematical point of view; (8) would give the most typical woollen thread if the yarn were level; but (7) would almost certainly yield the best all round thread. Roving, 109
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