A Rare Find
Since my first summer surveying job in the late 1960s, I’ve never considered another profession. What drew me to surveying was the chance to work outside; what has kept me in it is the bug you get from doing work you enjoy.
Innovation and invention have always been at the forefront of surveying--from the old hand crank adding machines to the modern computer. Some of the ideas have been good, some have not. Some were good for a time but became outdated very quickly, sometimes overnight. And others never managed to catch on. A few of these ideas have saved surveyors time even in light of current technology. One is the rare tracer rounds traversing instrument.
Machine at WorkIn the mid-1980s, I was researching visible lasers to use for triangulation for control. I theorized that if I could see a vertical laser from several known points it would be easy to triangulate them using a 1-second theodolite. I never found the laser I was looking for but I did find a gadget that was close--and unique. It was owned by a surveyor who had spent most of his career in the logging industry. He told me that he got great closures using this instrument and that he hated to part with it (but would for a price). The price seemed reasonable to me and I got the instrument in the mail a week later.
He said there were only three of these instruments manufactured. The instrument consists of several parts. The major mechanical component is a Thompson Center Contender .45 caliber pistol with a barrel machined to fit in a steel-mounting apparatus for a tribrach. This unit then sits on legs over a point just like a transit. The pistol is loaded with a “tracer round” and fired straight up. The tracer round, a pyrotechnic bullet manufactured especially for this instrument by Chief Industries Inc. of Grand Island, Neb., consists of a brass jacket surrounding the pyrotechnic. After being expended, the hollow brass casing floats harmlessly to the ground with no danger of fire.
I came across the man who sold me this instrument through one of those “I knew a guy who knew a guy” stories. Unfortunately, his name and contact information has long since been lost. I have one of the three rare instruments; the other two may be residing with some other surveyor, his children or in an attic somewhere. I would be interested to know if anyone else has one or has ever seen one. If you have, please contact me at firstname.lastname@example.org.