The formation has long been known to contain natural gas.
Thought they might contain some liquid or gas that was bad medicine.
The problem with using air is that it contains other gases than oxygen.
It is one of the provinces known to contain petroleum and natural gas.
"Charlie figured they contained gas merely by looking at it?"
Much food itself contains free gas distributed in pores within.
The spiral disk contains enough gas to make eight billion stars like the Sun, the astronomers said.
It was shaped like a large cigar and undoubtedly contained light gas of some kind.
A stage cylinder contains gas intended to extend bottom time.
One possibility would be to focus efforts on containing other greenhouse-effect gases.