The balloon was the first means by which man was able to ascend into the air. It is still going strong, for a knowledge of free ballooning is part of the stock-in-trade of the Navy lighter-than-air officer. A requisite to operation of the powered non-rigid airship is an understanding of the operation of a free balloon in air currents and in descent and ascent. Many an airship officer has successfully free-ballooned his craft to safety in emergency or without engine power. Here, at a lighter-than-air base, balloons ascend among the circling non-rigid Navy blimps.