Research during the year involved one graduate student and two principal investigators. Studies during this time concentrated on (1) preparing a review of polymer degradation and stabilization mechanisms, (2) developing a new technique for applying stabilizers to silk fabrics, (3) preparing samples to evaluate the effectiveness of several types of stabilizers, (4) artificially aging these samples by exposing to heat and light, (5) measuring the changes induced by aging on color, strength, and generation of ammonia and amino nitrogen, (6) measuring the ammonia nitrogen content of silk from a 16th century Flemish tapestry, and (7) analyzing a collection of 18th, 19th and early 20th century silk garments and fabrics for the presence of tin weighting agents and other metals. These items are described in the three preceding quarterly reports.