Drafting a map is all about making choices. The ability to make the best choices to meet the client’s needs is “what separates the wheat from the chaff”, to borrow an oft-used expression from one of my mentors.
To begin with, Earth is round, and the map is flat. Picture the act of gift wrapping a ball with paper – there is no perfect way to go about it. You must decide how to fold, crimp, or cut the paper in order to make it fully wrap the ball. When we make maps, we make a similar choice as we must decide which map projection to use, recognizing that none are perfect. A map projection is the method by which real Earth features are represented in a 2-dimensional plane.
Here in Connecticut, the official state map projection is conic. Imagine a translucent Earth, with a light source placed at the center. The imaginary Earth is surrounded with a cone, hence “conic”. When the light is turned on, the features of the Earth are projected onto the surface of the cone, hence “map projection”.
Mapmakers also choose which features to depict on the map and which ones to leave off, a process known as “generalization”. A town’s road map might contain the names, types, and configuration of the roads within a given area. However, it probably doesn’t include traffic signals, road signs, or fire hydrants. Even if it were a small town, those features would clutter the map and make it difficult if not impossible to use. However, if we were making a map of just one city block, it would be entirely possible (and relevant) to include signals, signs, and hydrants. The purpose and scale (size ratio) of the map are both important.
Franklin Surveys is frequently called on by our clients to prepare comprehensive property mapping with an extremely high level of detail. On those maps, we depict basically every site feature, up to and including the relief of the ground surface. But even then, we still generalize. People don’t show up on a map. Nor do animals or anything else that is readily movable, such as garbage cans or picnic tables. While it might be reasonable to depict a “picnic area” outline on a map, it doesn’t make any sense to definitively map the location of any feature whose position is temporary.
