Like the millipedes, centipedes are highly segmented (15 to 177 segments), but with only one pair of walking legs per segment (millipedes have two legs per segment). The head of a centipede has a pair of antennae, jaw-like mandibles (called forcipules) and other mouthparts.
Although compressed natural gas (CNG) is a fossil fuel like diesel, gas and coal, it is far different in terms of its impact on the natural environment.
Compressed Natural Gas (CNG) as a Transportation Fuel. Compressed natural gas, or CNG, is natural gas under pressure which remains clear, odorless, and non-corrosive. Although vehicles can use natural gas as either a liquid or a gas, most vehicles use the gaseous form compressed to pressures above 3,100 pounds per square inch. Most natural gas comes from three types of wells: natural gas-and-condensate wells, oil wells, and coal bed methane wells.