They are widely regarded as a world-class natural attraction containing marvellous stream passages formed by three rivers that sink underground on the slopes of Cuilcagh Mountain.
Fractionators take a mixed stream of natural gas liquids (the liquid stuff that comes out of the ground along with natural gas) and process it into pure products like ethane, propane and butane.
When activated, the five blocks ignite one after another for about a minute apiece, creating the steady stream of smoke that accompanies the natural smoke from the burned ballot papers.
Berkshire already has a stake in MidAmerican Energy Holdings , which "delivers our largest stream of non-insurance earnings" and will soon carry 8% of the natural gas in the U.S., he disclosed in this year's annual report.