| 摘要 |
<p>A plurality of boxes (1) with their bottoms opened are connected in a step form and submerged and fixed in water. A notch (2) is formed for the passage of air at the lower end of the connection side of each box (1). When air is blown into the lowermost box (1), the air is sent sequentially to the upper boxes (1) and stays inside all of the boxes (1). A diver can reach the depth of the sea by diving sequentially from the uppermost box (1) into the lower boxes (1) without using any air cylinder.</p> |
