Scanning electron micrograph of a sweat pore in skin from the palm of a man's hand. Like the opening to a deep cave, the sweat pore spirals down through the outer layer of the skin, or epidermis. It ends in a coiled sweat gland in the dermis or subcutaneous layers. The palm of the hand is one of the areas of the body richest in sweat glands. One quarter of the body's heat loss is achieved by sweating. Magnification: x130 at 35mm size, x900 at 8x10-inch size. Reference: MICROCOSMOS, figure 2.50, page 40.