Studies on the basic characteristics of South African Merino wool IV. Scaliness

Abstract

A study of the scaliness of South African Merino wool samples showed that the percentage differences in friction between the two directions varied from 3.0 per cent. to 130 per cent. At 70 per cent. relative humidity and 70°F. the mean was 66.0 per cent., the standard deviation 17.6 per cent. and the coefficient of variability 26.6 per cent. No difference in scaliness between different fineness groups within a staple was obtained. Between samples, however, a significant negative correlation of -0.3428 between percentage difference in friction and fibre fineness was obtained. The value obtained for a sample was concluded to be characteristic of the sample, and not of any particular group of fibres used for the determination. The regression coefficient of percentage difference in friction on fibre fineness was -2.30, a significant value, showing that on the average the percentage difference in friction decreases by 2.30 per cent. for every micron increase in the fibre fineness of the sample. The values for coefficient of friction for the different quality numbers of South African Merino wool are given. Wool from rams gave a lower value for scaliness concordant with a coarser wool. The scaliness of the wool grown by three sheep on constant feed decreased with age, though no corresponding changes in fibre fineness occurred.