A horizontal pipe 10 inches in diameter is covered with an inch of insulation that is 36% voids. The insulation has been soaked with water. The pipe is now drying slowly and hence almost isothermally in 80 °F air that has a relative humidity of about 55%. Estimate how long it will take the pipe to dry, assuming that capillarity always brings any liquid water to the pipe's surface. (H. A. Beesley)