An expression is derived for the strength of the blended yarn spun at optimum twist, in terms of the strengths of yarns spun from the two components at optimum twist. Good agreement between the predicted and observed values is found over a range of cottons and counts. The strength deficiency of the blended yarn is partly due to the differential response of the two components to twist. The evenness of the yarn is better than would have been expected, in contrast to the results for the yarn strength.
