Installment of the 'Fabric Analysis' series from Posselt's Textile Journal, February 1916, on preparing yarns and fibres for microscopic examination. It describes wool fibre structure (scales, medullary core, crimp), the difference between woolen and worsted yarns, and imperfect fibres such as untrue fibres and kemps. It also covers distinguishing hair from wool and briefly describes cashmere and mohair fibres, illustrated with micrographs (Figs. 20-28).