Mapping Cultural Changes in the Township of Canton: 1800-2004
Jonas Landes '05
The following section is provided
for a better understanding of each of the layers in my map service: http://slumap.stlawu.edu/website/historic_canton.
Each section will provide the source, potential applications, and complications
involved with each layer.
Houses
I digitized 5,675 individual points on maps from 1865, 1911, 1963, and 1982. Each point represents a house (Image 1). I digitized only homesteads and schoolhouses. Care was taken not to include businesses, churches, barns, or any other non-residential structures. Some buildings were obviously not residential in nature (Image 2). However, I may have included structures that were not residential and I may have excluded structures that were residential.
One particularly problematic issue was whether or not to include downtown buildings. Most main street buildings have both businesses and residences. I decided not to include main street buildings for three reasons: first there is no way of telling how many families lived in each building, second there is no way of indicating change in habitation, and third it is difficult to determine where one downtown building ends and another begins (Image 3).
Because of the differing scale and accuracy of the maps no points lined up perfectly. In fact, without personally visiting every house, it is difficult to determine if a point that existed in the same general area for all four time periods is the same structure (Image 4).
|
Year |
Color |
|
1865 |
Red |
|
1911 |
Green |
|
1963 |
Blue |
|
1982 |
Yellow |
Image 1
Image 2
Image 3
Image 4
Roads
I digitized three years of roads (1865, 1911, and 1963). Due to the different maps’ scales and surveyors’ mistakes none of the roads lined up perfectly. Unlike the houses, it is obvious that many of the different lines are actually the same road (Image 5). More interesting than noting map differences is noting where roads have shifted or disappeared. For example, Stiles road (sometime after 1865 and before 1911) is straightened out and the road connecting Route 310 (after 1911) was removed (Image 5).
Image 5
Railroads
There are 2
throughway railroads and 3 short branch railroads in the
Name of
This layer highlights all population centers that were named on any of the three maps. The names of places not only changed but also emerged and disappeared. In the attributes table of each population center I provided the name of the center for each map year as well as listed the establishment of the first post office.
Houses within 60m of Wetlands
Houses from all years within 60 meters of Wetlands were selected. Not surprisingly the number of houses near wetlands declines over time (Image 6).
Image 6
Houses within 100m of Upper and
I selected
all houses within 100 meters of Upper and
Major waterways
I digitized
the path of the four major waterways in the
Hydrology
Hydrology data was obtained from St. Lawrence University’s database; (T:Atlas).
Wetlands
Wetlands data was obtained from the
U. S. Fish and Wildlife wetlands survey of 1994. Because the wetlands survey, a
national project, was conducted using aerial photographs, there are obvious
errors that were overlooked by the surveyors, such as the fact that the
Image 7
Real Property
I took the St. Lawrence County Real Property Data and reorganized the features so that properties with houses were divided into categories by the year they were built. This layer is helpful in determining which homes still exist as well as determining areas of growth (Image 8).
Image 8
State Lands
From the
Real Property Data I extracted all state owned lands within the boundary of
Density Analysis
I took the
density of all houses, roads, and railroads over the three maps. This
information determines where greatest areas of human impact and change are.
This information can also be used to compare changes in number of houses to
proximity of roads or railroads. I only conducted density analysis on the
layers that I digitized.
This is the
simplest and most straightforward layer I created. This is merely a square
boundary marking the
1865 map of
I took a digital version of the DeBeers Atlas of St. Lawrence County and geo-referenced it. Geo-referencing is the act of giving a map (or image) scale and universal coordinates. I chose crossroads and junctions that were unlikely to have changed in the last 140 years. The accuracy is 16+/- meters.
1911 USGS map of
I clipped
and then geo-referenced three (Ogdensburg,
1963 USGS map of
The 1963 USGS
topographic maps did not need to be geo-referenced, only clipped. To create the
Elevation
I obtained
the elevation data from T:\Atlas\Elevation\dem. However, to make it usable I
mosaiced and then clipped all the 7.5-minute elevation maps that fall within
Beers,
S. N. 1865. New topographical atlas of St. Lawrence Co.,