As we were paddling in to the dock on the lake, a helicopter flew overhead and low, carrying something beneath it. From a distance I thought it was a water bucket (for fire-fighting), but nearer, it looked like a missile. The copter then landed just above the dock. I wandered over to see what it was and found out it was a magnetometer. The copter and crew (two guys) are surveying a parcel of land nearby for a mineral company, measuring magnetic fields (passive and active -- the McPhar device produces a magnetic field) and radiation. The helicopter is based at the lodge where our excursion left from to save time -- the parcel to survey was nearby and it'll take several days (or longer? I don't recall) to complete the work.
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