Wiktionary
natural gases
n. (natural gas English)
Usage examples of "natural gases".
We never figured out if the natural gases here could be synthesized.
The morning's talks with experts at the Museum had provided a more-or-less expert opinion that the book was probably really a century or more old, but had been less helpful in offering support for the theory of noxious chemicals or natural gases.
There may be other natural gases present as well which are not so easily recognizable, and even more flammable.