Blisworth Limestone Formation relationship to the Jurassic ridge, to the west of Peterborough. (BGS sheet 157) Around Towcester it reaches a thickness of 9m. (Hains & Horton p. 85) Blisworth limestone is used as a building material, in particular as blocks of stone. Lilford Hall in Northamptonshire is made from Blisworth limestone. Blisworth Limestone Formation The Blisworth Limestone Formation is a geological formation primarily consisting of limestone deposited during the Bathonian stage of the Middle Jurassic, found in the Jurassic ridge which extends north and south through England. It was laid down in the shallows of the Jurassic sea and is part of
Pennsylvania Canal Tunnel Pennsylvania Canal Tunnel The Pennsylvania Canal Tunnel was the Pittsburgh terminus of the Pennsylvania Main Line of Public Works, a transportation system that involved other early tunnels. Construction was authorized February 8, 1827, and the tunnel was completed November 10, 1829. The canal crossed the Allegheny River on a covered bridge aqueduct, later replaced by John A. Roebling's first suspension bridge, the Allegheny Aqueduct., the canal traveled underground through most of downtown Pittsburgh, under Grant's Hill, to end in a lock leading to the Monongahela River. The original plan was to connect with the C&O canal at the Monongahela River,