Mystery stations?

[Amygdaloid]

There are several strange tripod like stations along the Keweenaw Waterway in the Houghton/Hancock area of Michigan's UP. I first saw these when I was in college getting a degree in Surveying at Michigan Tech in the 80's, but even the Surveying Faculty did not know where they came from. I never found any identification marks on them, and I never found a benchmark disk below the center pipe, although there is sort of a pipe cap. I found about a half dozen in my college days, but several have been removed by road construction and development since then. They have been around for a long time, I saw pictures of them in an old Michigan Tech yearbook from the 30's or 40's. I always assumed they where used in a triangulation project given there locations in relatively high points that straddle both sides of the waterway, but who placed them, how they where used, and why they where made so robust and permanent has remained a mystery. Can anyone shed any light on them?

 

Station 1

Station 2

[Bill93]

They do look like triangulation points. I had never seen such an arrangement, but I don't have a lot of experience. It looks like there is room for someone to set up a tripod and instrument under the pyramid, and the upper pipe could be sighted on or could hold a taller target.

 

This identification would be stronger if we knew that these contraptions had footings to keep them stable, and either a means for hanging a plumb line centered in the pipe or else a point monumented in the ground to set up over.

[Amygdaloid]

The one in the snow was tall enough to stand under, so you could set up under it. The one in the other photo was much shorter so I doubt that would be possible. They are permanently attacthed to a concrete base, so they are stable (they have been around at least 50 years). I intend to look for more of these and get better photos, but with winter fast approaching that may not happen until next summer (they get LOTS of snow up there!)

[kayakbird]

Amyqdaloid,

 

Interesting structure. Hope some definitive information pops up here. I'm wondering if they have something to do with the 1930's re-survey of the USLS points? kayakbird

[+jwahl]

If these things are on points readily visible from the waterway, they could have been part of a system of navigational aids. These would have been sighted by ships using various techniques to determine a position or a line. They might be falling into disrepair with the advent of GPS. When they were in use, I would expect a large red and white target to be mounted on top.

 

This is however, just a guess.

 

- jlw

[+GEO*Trailblazer 1]

What type of structures were the LORAN on?

 

Just another guess.

 

Edit:

May be SHORAN

Structure

 

SHORAN, which operates at 300 MHz, requires an airborne AN/APN-3 set and two AN/CPN-2 or 2A ground stations.[clarification needed] The equipment onboard the aircraft includes a transmitter, a receiver, an operator's console and a K-1A model bombing computer. The transmitter sends pulses to one of the ground stations and the system calculates the range in statute miles by clocking the elapsed time between transmitter pulse and the returned signal. The system was intended for use in navigation, but it became obvious that it would work well for blind targeting during bombing runs in poor visibility. The setup made up of the K-1A bombing computer combined with the navigation system was the first SHORAN. The SHORAN system is designed so that as the aircraft faces the target, the low-frequency station should be on the left, and the high-frequency station is on the right. This allows the computer to triangulate the two stations and the target.

Edited November 20, 2009 by GEO*Trailblazer 1