two warps of 65 35 polyester cotton 35 39 s cotton count yarn these two warps were woven on projectile looms and compared with warps from the same yarn set sized without the addition of the colloidal silica yarns collected from these warps exhibited lower tensile strength in laboratory testing and lower weaving performance than the warps sized with the composition which did not contain the colloidal silica no polyester colloidal silica complex of the invention was present the effects of the abrasive agglomerated silica were apparent in lowered tensile strength and weaving efficiency the compositions of example 1 and example 2 were repeated on 1 2 set of yarn each of 50 50 polyester cotton 35 39 s cotton count yarn the two 1 2 sets were woven on shuttle looms and compared directly by both total efficiency and industrial engineering studies the 1 2 set sized with the composition of example 1 exhibited a weaving performance of 91 6 and a warp stop level of 0 804 hour the 1 2 set sized with the composition of example 2 exhibited a weaving performance of 95 2 and a warp stop level of 0 497 hour 200 lb of carboxymethylated starch and 12 lb of kettle wax were cooked and applied to 100 cotton yearn 14 39 s cotton count industrial engineering studies of shuttle weaving indicated that a warp stop level of 0 83 hour was obtained with this composition.