July 1, 2006
Are surveyors mappers? Are mappers surveyors? Ask a group of surveying and mapping professionals and you are likely to get a variety of answers, such as: "Heck, mappers aren't surveyors."
"All surveyors make maps, therefore they are mappers too." "Not if they are GIS professionals." "Mappers make maps; surveyors do surveys."
Given the discussions about whether GIS activity is a function of surveyors, mappers or both, I think a lot of practitioners in this profession care about the specific definitions of these groups. Read on and decide what you think about this issue.
How one answers the questions posed above depends a lot on how one defines surveying and mapping. Here are excerpts from Merriam-Webster's online dictionary:
Map-1 a : to make a map of"¦ c : to make a survey of, for, or as if for the purpose of making a map d : to assign (as a set or element) in a mathematical correspondence <map a set onto itself> <map picture elements to video memory>"¦
Survey-1 a : to examine as to condition, situation or value"¦ 2 : to determine and delineate the form, extent and position of (as a tract of land) by taking linear and angular measurements and by applying the principles of geometry and trigonometry 3 : to view or consider comprehensively"¦
What I think is most interesting is that the word "survey" is used in the definition of mapping. It could be argued from this that all mapping activities use surveying techniques to get a desired result. I have always regarded surveying as part of the mapping continuum and view surveying as a precise subset of mapping functions. Part of my reason for this comes from my observations of the way measurements are made and the kinds of measurements or observations made by people who call themselves surveyors or mappers exclusively.
I say that surveyors are part of the mapping continuum because I find that surveyors are focused on measurements. They are theoretically interested in making maps, but most consider their premier product to be maps or other reports that show the measurements they have taken directly or indirectly; that is, the measurements themselves are important features of their maps. Mappers, on the other hand, also make measurements, but they are focused on the overall picture. Thus, rarely will the values of their direct (or indirect) measurements be shown. (Of course, if measurement information is desired, it can generally be determined by using a protractor and scale.) Another key feature of the way mappers work is that although they make measurements, they place equal if not higher value on the attributes of the things they measure. (I should mention that there is a group of people-and I'm one of them-who regard themselves as surveyors and mappers. Surveyors often think that they do surveys yet they also make maps.)
Some of you may say that the definitions I've referred to above are general definitions, that we should refer to technical ones. Here are definitions from the Definitions of Surveying and Associated Terms, revised 2005, published by the American Congress on Surveying and Mapping.
Mapping-No definition given for this verb. (I thought it interesting that "mapping" is not defined-perhaps giving away its surveying-centric roots?)
Map-A representation on a plane surface"¦ of a part or the whole of the Earth's surface"¦. A map should contain a record of the projection upon which it is constructed.
Surveying-1 The science and art of making all essential measurements to determine the relative position of points and/or physical and cultural details above, on or beneath the surface of the Earth and to depict them in usable forms, or to establish the position of points and/or details"¦ 3 An acquisition and/or accumulation of qualitative information and quantitative data"¦
Survey-"¦3 v. To measure distances, angles and heights to determine the relative locations of points under, on or above the Earth. 4 v. To inspect or investigate something in order to determine its state or condition.
So what should we draw from all of this? Well, the first thing is that surveyors and mappers both make measurements of the Earth's surface. We should also agree that surveyors make maps, whether those maps depict property boundaries or topography or other sets of features. A map should contain a record of the projection upon which it is constructed; however, few surveyors apply these projections (it's a good thing they aren't required). So, it seems hard, at least to me, to define one of these terms (surveying or mapping) without using the other. Merriam-Webster actually records that mapping is "to make a survey," whereas Definitions refers to surveying descriptions that sound a lot like maps or mapping: "determine the relative position of points and/or physical and cultural details"¦of the Earth," and "depict them in usable forms."
To me, much of surveying is mapping and much of mapping is surveying. Perhaps what distinguishes them the best can be found in both Merriam-Webster and Definitions. And that is that surveying includes an element to ""¦examine as to condition, situation or value"¦" or "to inspect or investigate something in order to determine its state or condition." Neither of these sources refers to surveying as the determination or delineation of property boundaries. To me that is an obvious oversight. This aspect of the surveyor's function is a practically worldwide characteristic. One might argue that the mention of "tract" in Merriam-Webster's definition might be an implicit recognition of it. Finally, there is one final aspect of surveying covered in Definitions that is not included in the discussion of mapping: "establishing the position of points and/or details." It appears clear that mappers do not (primarily) set out points.