helium
hee lee uhm
- n a very light colorless element that is one of the six inert gasses; the most difficult gas to liquefy; occurs in economically extractable amounts in certain natural gases (as those found in Texas and Kansas)
- Liquid hydrogen is used to absorb the heat from cooling helium.
- Why not use helium, which weighs only one-seventh as much as air, to inflate airplane tires and thereby save precious cargo weight? This idea might have occurred to any ten-year .
- The production of helium, a light, rare gas, has already become a prime requisite for aviation because it is non-inflammable and saves dirigibles from fire hazard.