They could only go through particular places called water gaps. On the other hand, the valleys in central Pennsylvania are linked from the Susquehanna River and its smaller rivers. This allowed for canals to be built in the 1830s. By clicking “Acknowledge All Cookies�? you comply with the storing of https://www.tjcyindustrialchem.com/news/what-is-sodium-tripolyphosphate-stpp-used-for.html