['In', 'the', 'early', '20th', 'century', ',', 'the', 'introduction', 'of', 'jack', 'sinkers', 'revolutionized', 'the', 'knitting', 'industry', '.', 'These', 'critical', 'components', ',', 'which', 'are', 'plates', 'on', 'the', 'ends', 'of', 'jacks', 'on', 'the', 'knitting', 'frame', 'acting', 'as', 'depressers', 'of', 'the', 'yarns', ',', 'ensured', 'a', 'smoother', 'operation', 'and', 'improved', 'the', 'quality', 'of', 'knitted', 'fabrics', '.', 'The', 'precise', 'functioning', 'of', 'jack', 'sinkers', 'allowed', 'for', 'greater', 'consistency', 'in', 'stitch', 'formation', ',', 'making', 'them', 'essential', 'for', 'high-speed', 'knitting', 'machines', '.']
[[9, 10, 'Textile Machinery']]