<P> The system has been explored and mapped by cave divers of the Jacob's Well Exploration Project and has been shown to consist of two principal conduits . One passageway measures approximately 4,500 feet (1,400 m) from the surface and a secondary one extends approximately 1,000 feet (300 m) in length from the point where it diverges from the main conduit . </P> <P> The cave is also an attraction for open - water divers, some of whom are inexperienced with the specialized techniques and equipment used in cave diving, which has resulted in eight fatalities at this site between 1964 and 1984 (seven men and one woman). </P>

Why is it called jacob's well in texas