['The', 'equational', 'box', 'is', 'a', 'notable', 'invention', 'by', 'Houldsworth', ',', 'designed', 'specifically', 'for', 'the', 'spinning', 'frame', '.', 'This', 'device', 'plays', 'a', 'crucial', 'role', 'in', 'the', 'textile', 'industry', 'by', 'allowing', 'for', 'the', 'gradual', 'adjustment', 'of', 'the', 'bobbin', 'speeds', 'according', 'to', 'the', 'specific', 'requirements', 'of', 'the', 'spinning', 'process', '.', 'The', 'operation', 'of', 'the', 'equational', 'box', 'leverages', 'cone', 'pulleys', 'and', 'differential', 'gearing', ',', 'which', 'work', 'together', 'to', 'modify', 'the', 'drive', 'of', 'the', 'bobbins', ',', 'ensuring', 'that', 'each', 'bobbin', 'can', 'operate', 'at', 'an', 'optimal', 'speed', '.']
[[1, 2, 'Textile Machinery']]