built on the principle, which was later adopted by the railway, of dividing the total distance by the total descent in order to determine the grade. The Lehigh Navigation Company, then suffering from an unprecedented dearth of water, adopted White's invention of sluice gates connecting with pools that could be filled with reserve water to be drawn upon as needed for navigation. By 1819, the depth of water between Mauch Chunk and Easton was obtained. The two companies were immediately amalgamated under the title of the Lehigh Coal and Navigation Company. By 1823, the two companies delivered over two thousand tons of coal to market. Lehigh Navigation Company Having displayed great technological skills by creating the world's first iron wire suspension bridge, which spanned the Schuylkill River at their wire works, White and Hazard schemed with other industrialists to secure a reliable source of anthracite. To move the coal to market, they entered political negotiations to acquire rights to tame the turbulent and rapids-ridden Lehigh River for navigation. By 1817–18, they had organized the separate Lehigh Navigation Company and had written stock flyers announcing plans to deliver barge loads of coal regularly to Philadelphia by 1824. The LCMC had trouble delivering Anthracite to Philadelphia at costs cheaper than imported Bituminous Coal from Britain or Virginia. Their last expedition had been sent out in 1813 during the war & blockade caused bituminous shortages, and by the time five arks were sent down river, three sank, leaving the directors of LCMC disgusted and unwilling to fund more losses. The company began to prepare plans and surveyed sites, and when the state legislature approved the river work in 1818, immediately hired teams of men and began to install locks, dams, and weirs, including water management gates of their own novel design. A brief history of the navigations beginnings as Brenckman related in 1884: The canal head end needed a location where barges could be built and timber and coal could be brought into slack water. The challenge was to do it above the gap made by the east end of Mount Pisgah, a hard rock knob that towers 900 feet above the Lehigh River towns Jim Thorpe (formerly Mauch Chunk) to the towns west, and Nesquehoning to its north. Both towns are built into the flanks, the traverses, of the mountain, with flats along the river banks. (A few decades later, railroads would