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Stereogram 3. Route location over rolling farm land. A route location of 
this character, through rolling topography where there is a variety of agri- 
cultural use of the land, is established while the photographs are examined 
stereoscopically and photographically interpreted. Available topographic maps 
are especially helpful if used in conjunction with the photographs, as the 
reconnaissance surveys are made to determine the route alternatives. Together 
the maps and photographs are ideal complementing companions, the maps provid- 
ing position and dimensions and the photographs the required qualitative infor- 
mation. This route contains uniform alinement and gradient while descending 
to and ascending from the drainageway, attains, as much as practicable, a 
near normal crossing of the drainageway and existing road to keep structure 
costs to & minimum, avoids severance of property by following existing prop- 
erty lines and thus decreases inconveniences to property owners and costs of 
right-of-way, and avoids the sink hole areas where the limestone has been 
dissolved and drained away and humus is gradually replacing it.