Eight-page encyclopedia entry on silk ("Seda") in Spanish. It covers the structure of the silkworm cocoon and its thread, the killing and classification of cocoons, and silk reeling machinery (including Robinet's reeling machine), with figures. It then treats throwing and twisting of raw silk (pelo, trama, organzin; circular and oval throwing mills), stain removal and cleaning of silk fabrics and ribbons, and chemical tests distinguishing silk from wool and cotton.