Two energy companies known for their fracking technologies are going after public money even as the drilling technique continues to receive negative publicity.

FORBES: Frackers Drilling for IPO Dollars

The drilling technique, which uses sand, water and chemicals under high pressure to extract oil and natural gas from rock formations, has helped Eagle Ford oil production grow by 184% last year compared with 2011, according to the Railroad Commission of Texas, which regulates the state's oil and gas exploration and production.

WSJ: From Oil, a Land Rush��WSJ Mansion

And there, too, Bissell had a flash of inspiration: Adapt the new technique used for drilling for water to the recovery of oil.

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The technique they developed, called hydraulic fracking, involves drilling 5, 000-9, 000 feet below ground (in the Marcellus shale), and then moving horizontally into the layers of shale rock where the hydrocarbons lie.

FORBES: Shale Leases: Promised Land