A self-actor minder (spinning), aka mule spinner, was a spinner who minded a pair of spinning mules which were arranged facing each other, that is spinning machines with an intermittent action which simultaneously drew and twisted cotton, wool, etc. in to yarn or thread and wound it into cops.
A self-actor minder (doubling) aka a twiner minder, or twiner spinner, operated machinery which controlled the working of a twining frame, and supervised the twiner piecer, and twiner spooler.
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