At the back of the diving case is a recess and in it is installed a compact but powerful pump, which sucks from the feet of the suit all leakage and forces it at once outward. This pump is worked by compressed air, and the air, after performing its mechanical part of driving the pump, is exhausted into the suit for the diver to breathe and then passes to the surface through the free space in an armored rubber tube, within which are led down to the diver the compressed air pipe for driving the pump, and the electrical connections for telephone and lamp. Thus the diving case receives a thorough ventilation, and it has been found that should the pump fail to work for a number of minutes there would still be enough air remaining in the diving case and the tube space to supply the diver’s needs for at least the length of time he is being hauled to the surface. During the experiment in Long Island Sound the pump was stopped for ten minutes, while the diver was at a depth of 100 feet. He suffered no inconvenience, and when the compressor again was started he was lowered to a depth of 212 feet. If such a condition as failure of the pump to work for ten minutes had arisen during a descent in the old elastic diving dress the result must necessarily have been fatal. Nor is a delay necessary in hoisting the diver clad in the new diving apparatus to the surface. According to the British Admiralty regulations, should a diver go down to a depth of 204 feet, the time of his ascent must be not less than one hour and a half. In the Long Island Sound experiments the diver was hoisted to the surface in eighty-seven seconds. He was totally unaffected by the abrupt change in pressure, although the deepest he had ever been was ninety feet, and on that occasion he had suffered from bleeding at the nose and ears. Why do We Smile when We are Pleased? We smile to express our pleasure. When you meet a friend on the street you smile as you greet him. This is an indication of your pleasure at seeing him. This is often caused by an unconscious nervous action produced by the impression the occurrence creates on the brain. You do not have to think about smiling, but the muscles of your face contract and give you that pleased look without any effort on your part. Why do Some of Us have Freckles? Some people have freckles, when others do not, because all skins are not alike, just the same as eyes are not all of one color. People with certain kinds of skin freckle more quickly when the skin is exposed to the sun. The action of the sun on their skin causes small parts of the second layer of skin to give out a yellow or yellowish brown substance. Freckles are most common in persons of fair complexion and hair. In some cases freckles are permanent, but in most cases they disappear with the coming of cold weather. Pictorial Story of the Steel Industry [Illustration: MINING ORE, ISLAND OF CUBA.[36] (See page 415.)]