Problems & Solutions

Problems and Solutions. The Blue Ridge Tunnel. , Tunneling in the 1850s often required timbered vertical shafts. Workers were hoisted down in buckets to the tunnel level, where they blasted horizontally into the mountain. Meanwhile other men blasted into it sideways from both portals. In theory, shafts made tunneling go faster. But chief engineer Claudius Crozet thought they were impractical for the Blue Ridge Tunnel. The passage would be 700 feet below the mountaintop. Digging shafts that deep was a waste of money because they would not advance the speed of the work , by the time they were in place, blasters from the sides would have reached the tunnel center. As Crozet wrote, "shafts are more frequently used than useful." , Newspapers that complained about delayed completion of the tunnel questioned Crozet's decision. But lack of shafts didn't slow construction. Unavoidable use of fickle gunpowder, manual drilling and manual removal of debris did. The tunnel project preceded the invention of stable dynamite, drilling machines and motor-driven muck cars by decades. , In 1849, Crozet doubted that water in the tunnel would be an issue. By 1853, though, he admitted it was "suddenly very troublesome." He fashioned a siphon from connected, cast iron pipes, stating it was 2,000 feet in length and the longest on record. In fact, an engineer determined in 1911 that it was 1,792 feet long. Regardless, the siphon eventually pumped out two-thirds of the water at sixty gallons a minute. A horse-powered pump removed the rest. , "It was altogether a somewhat bold experiment," Crozet wrote about his siphon, "and I am pleased to see it answer a good purpose." , Another construction snag developed when seasoned timber proved unavailable for the South River Bridge in Waynesboro. Undeterred, Crozet chose to build an iron bridge instead. Designed by Wendel Bollman, it was fabricated at Tredegar Iron Works in Richmond and in place by 1853. Crozet declared it a "firm and elegant structure." , Crozet was certain that post-blast ventilation of smoke would be a problem. Indeed it was. Based on his study of an English ventilation device, he employed several machinists to make and maintain a version of it. By 1853, the chief engineer could report that a "constant supply of fresh air is afforded to the hands."