Arkansas summer field camp included three mapping projects that each lasted about ten to fourteen days.  One such project was the mapping of a quadrangle using plane table and alidade.  The project requires two people, my partner a young man named Roy.  We started the project as friends.  The two weeks of our partnership proved almost disastrous, rocky even - to use a very bad pun - to that friendship.

The field mapping project began innocently enough.  The rolling hills of northern Arkansas are called the Ozarks and our camp lay in the heart of that ancient range.  Our project: map an area known as Love Hollow.  Yes, the mailbox fronting the only house in the area bore the name I.M. Love.  I am not making this up!

An alidade is similar to a surveying transit that sits on a square piece of wood (plane table) atop a tripod.  A topographic quadrangle map is mounted on the plane table and this topo map becomes the base for the geologic map created systematically by the two mappers.  The first mapper operates the plane table and alidade.  The second mapper carries a long pole marked with incremental numbers.  The pole man, interestingly enough, is the most important member of the team because he must locate the points of geologic interest.

The project begins like this: the alidade operator sets up a base station, preferably on a hill with visibility in many directions.  He orients his position on the map and then sends the pole man some distance away, hopefully to locate an outcrop of bare rock.  It was at this point during the first day of the partnership that the friendship between Roy and I first became strained.

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