The wooden trough that carries the Canal over the aqueduct must be very strongly constructed and heavily braced in order to withstand the great weight of the water flowing through it. In the case of the Rexford Aqueduct, pictured here, almost 400 tons of water must be supported.
Just a few miles west of the Cohoes Falls and lock system, the River makes a broad curve from a north-south direction to east-west. To avoid major erosion of the bank holding the Canal (on the east and south side of the River) which was exposed to the faster moving water on the outside of the broad curve, two aqueducts had to be built. The first, east of the curve, carried the Canal from the south side of the Mohawk to the north. The Canal ran westward along the north shore of the River for several miles through southern Saratoga County and then, a second aqueduct at Rexford was constructed to carry the Canal back to the south shore of the River. An additional factor that justified the expense of two aqueducts was that if the Canal were along the north side of the River, the snow on those south facing banks would melt sooner than if the Canal were in the shade on the south side. Thus, the Canal could open earlier in the spring.
This engraving depicts the aqueduct over the Genesee River in downtown Rochester. In the foreground are the remains of the original aqueduct, which was replaced in the 1836 Enlargement.
Tuesday August 6, 1833
"About one we entered [Rochester] which looked to me like a city filled with business and
wealth. The Canal runs along the east side of the river (Genesee) for half a mile before it
crosses, which is done by a splendid aqueduct of red stone having 11 arches. ... Its length is 800
feet."
Monday August 12, 1833
"I found myself in Rochester very early this morning where we remained the bigger part of the
day, which was rainy. I, however, notwithstanding the weather, made shift to visit some [of] the
mammoth flour mills which are now turning with all their machinery. These mills generally
have from six to nine runs of stones which are driven by two or three great wheels. Everything
about these flour mills, as it respects manufacturing the flour, is carried on by machinery; even
the wheat is taken out of the boats and carried to the place where it is cleaned and prepared for
grinding. The flour is carried by means of elevators from top to bottom until cool and then into
the bolts, which is the last process before barreling. All these various movements were formerly
performed by manual labour, but as time brings improvement in the various arts what was once
the labour of weeks in the hands of men is now done in days by the aid of mechanics."
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