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 absurd as to wear cotton outer clothing in Northern states during the eight cold months.

Black clothing absorbs twice, blue almost twice, red and yellow almost one and a half times, as much heat as white clothing (Exp. 10). Which material protects best from radiant heat? (Exp. 9.) Because large blood vessels are near the surface at the neck, wrists, and ankles very thin or no covering at those points aids greatly in keeping the body cool. High collars, long sleeves, and high shoes are unhealthful in warm climates and in summer. What objection to black shoes in summer? Patent leather? Show how women dress more sensibly in hot weather than men.

The kidneys are located on each side of the spinal column in the "small of the back" and extend slightly above the level of the waist. They are bean-shaped organs about four inches long (Fig. 26). The kidneys of a sheep or ox closely resemble those of man. They are outside of the peritoneum (Fig. 99) and attached to the rear wall of the abdomen. A large artery (12, colored Fig. 5) goes to each kidney and divides into many capillaries which surround tubules in the kidneys (Fig. 27). The secretion, containing nitrogenous impurities of the blood, is continually being deposited in the tubules, which take it to a funnel-shaped cavity at the inner edge of the kidney (Fig. 26). From this cavity a white tube called the ureter leads down to a storage organ in the pelvis called the bladder.

RA, renal artery; Py, pyramids surrounding hollow space from which the ureter (U) leads the secretion to the bladder.