m Tyngsborough, and the framing done at Billerica in 1827. Eight days sufficed to remove the timbers of the lock and aqueduct with the piling that supported the latter.
All the iron was saved, and the wood sawed into four foot lengths, piled in lots, and sold at auction.
The old abutments of great boulders needed no repair.
The wooden piling was replaced by three pieces of split granite, and the season being favorable, the work had progressed so rapidly that these neared completion in January.
The total cost of the aqueduct and lock thus rebuilt was nearly $7,000. The stone was sunk into the river's bed, and so well did these men perform their work that no repairs were needed, when forty-five years later the Boston avenue bridge was built upon it and served the public for twenty-seven years. Those who may have witnessed its demolition and the construction of the graceful granite arch now spanning the river, and remember the difficulties then encountered, can readily see that wi