Plain-woven cotton, regenerated-cellulose rayon, cellulose-acetate rayon, silk, wild silk, and wool were washed separately by hand in 0.5 percent solutions of neutral olive-oil soap, silicated soap, or sulfated alcohol for five minutes at room temperature, rinsed until the rinse no longer foamed and dried in air and diffused light at room temperature. After ten, twenty, thirty, forty, and fifty washings all the fabrics were analyzed for ash, percentage of light absorbed, shrinkage, wet warp breaking strength, elongation at breaking load, and weight. The silks and wool were analyzed for total nitrogen and sulfate sulfur, the wool for total sulfur, and cellulose acetate for acetyl;The acetyl value of the cellulose-acetate rayon increased by 0.5 percent in ten washings but then remained constant;With each detergent the ash of the cellulosic fabrics decreased and that of the proteic fabrics increased with increasing number of washings. The increase in ash for wild silk and wool was greatest with silicated soap and least for wool with sulfated alcohol;Total nitrogen of the residual wild silks shows loss of non-nitrogenous sizing during washing, that of silk and wool the increased weight of the residual fabrics;Repeated washings bleached cellulose, and this effect was greatest with silicated soap. Silk, wild silk, and wool became darker upon repeated washing with sulfated alcohol;Fabrics other than wool shrank but little in any of the detergents;The wet strength of all the fabrics decreased with increasing number of washings in each of the three detergents. The wet strength of silk decreased 76 percent with sulfated alcohol, ten percent with silicated soap and 24 percent with soap in fifty washings. Wild silk lost 74 percent of its wet strength with sulfated alcohol, nineteen percent with silicated soap, and 21 percent with soap in fifty washings;The residual sulfur of wool washed with silicated soap or soap remained constant and that of wool washed with sulfated alcohol increased. Silk and wild silk also retained sulfate sulfur from the sulfated alcohol;The loss in weight of the cotton and wild silk fabrics upon washing is explained by their loss of sizing. Regenerated cellulose, contrasted with cellulose acetate, gained slightly in weight and upon washing. Wool gained more in weight than silk with each of the three detergents.