BEFORE TECHNICAL OUTERWEAR-- "What fabrics best insulate the body against the loss of heat? Tests demonstrate, as expected, that an open-weave cotton fabric has the smallest insulation value. A dense cotton cloth gives somewhat more protection, and wool still more. But insulation value declines greatly when fabrics are damp; for wet cotton flannelette, the heat loss is greater than when the test surface has no cover at all. The study suggests these avenues of research in winter clothing: underclothing that will not readily absorb water, garments that will hold quantities of air in extremely small bubbles, and quilted clothes made of a batting of chicken feathers and cotton."