Blisworth Limestone Formation today in the seas off the Bahamas (Kirkaldy p. 59). Much of it also contains marine shells, notably of oyster. Subsequently, the site was submerged less deeply so that the overlying Blisworth Clay was deposited in brackish conditions. (Gallois p. 20) The stratum is known as Blisworth Limestone because it was first studied at Blisworth in Northamptonshire when the Blisworth tunnel was being dug for what is now called the Grand Union Canal. The tunnel finally opened in 1805. Blisworth limestone is a generally thin but widely spread deposit in eastern England. It becomes thicker as one progresses southward from
Cincinnati and Whitewater Canal Tunnel the portion of U.S. Route 50 that travels over the tunnel. Despite the efforts spent on building the Whitewater Canal, it was abandoned in 1856 after numerous floods had destroyed much of its length. This resulted in the abandonment of the canal tunnel, a period of stagnation that ended in 1863 when a railroad company began a twenty-five-year period of using it as an ordinary rail tunnel. Since the rail line ceased operation in 1888, the canal has become completely unusable, having silted up almost all the way to the ceiling. However, the tunnel has not been completely forgotten; the