MADISON — The little S&L Engine That Could, Essex Savings Bank, continues its stealth march to the west. On December 14 the bank will open its first branch in Madison, at 99 Durham Road (a/k/a Rt. 79). Bank officials and employees of the new branch (obviously) as well as town dignitaries will be on hand for the 9:30 a.m. ribbon-cutting. Founded in 1851, the mutual savings bank has branches in Chester, Deep River, Essex, Lyme, Old Lyme, Old Saybrook and Westbrook. The bank annually invests ten percent of its after-tax net income in community organizations voted to be worthwhile by bank customers.