Based on the info here it looks like Schenectady or Scotia are good candidates. The mention of the bridge over the main channel might argue for Scotia. http://zircon.geology.union.edu/Mohawk_River/ 170_yr.html#%221910:%20The%20Massive%20Gorge%20at%20Crescent%22 http://zircon.geology.union.edu/Mohawk_River/170_yr.html#Ice%20jamming Margaret