Complex sentence: White's bridge company operated from a factory on the Beaver River in New Brighton until it was destroyed by fire in 1878, when the company relocated across the river to Beaver Falls and restructured as the Penn Bridge Company.
Split into simpler sentences: White's bridge company operated from a factory on the Beaver River in New Brighton until the factory was destroyed by fire in 1878. After the fire, the company relocated across the river to Beaver Falls and restructured as the Penn Bridge Company.