Abstract: A desiccating device includes a rigid container having an end sealed by a selectively permeable membrane, operative to admit water vapor into the container, but not allow water to pass out of the container. A desiccant separates water from water vapor that has entered the container. A removable impermeable membrane seals the container, and prevents water vapor from entering the container when the impermeable membrane is in place. A reinforcing member having apertures is placed above the selectively permeable membrane, enabling a thinner and weaker selectively permeable membrane. The container shape defines angles of less than 90 degrees, as in a triangle or other truncated rectangle, where the device may be placed in a corner, projecting into the area to be dried less than a rectangular or circular container.