1856 Map... What does SM mean?

IMAUDIGGER

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Iā€™d guess in your instance, itā€™s likely referring to ā€œBench Markā€ the numbers either being the elevation, or the name of the survey monument.

B636AF00-D977-45F9-B609-FA6E0574B089.jpeg

In this case itā€™s a triangulation survey marker located at the top of a mountain.
 

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franklin

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BM stands for Boundary Marker. SM stands for Survey Marker.
 

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IMAUDIGGER

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Iā€™d have to respectfully disagree.
When any of the following have a third order or better elevation assigned AND are monumented with a tablet, they are labeled as ā€œBMā€ (bench mark);

1.) Boundary monuments (square with dot)
2.) Horizontal control (triangle)
3.) Vertical control ( x )

Itā€™s the vertical elevation aspect that triggers the annotation.
Boundary monuments donā€™t typically have elevations assigned, nor are they usually numbered.

Here is what you will typically find at one of those locations labeled ā€œBMā€...at least thatā€™s been my experience. Note ā€œB.M.ā€ embossed on the first tablet.

C2CB3892-86B9-4AAE-A472-D6794643237C.jpeg

1ABAD5A9-0652-4240-AE71-6DC84EDBB8C4.jpeg
 

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teleprospector

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Iā€™d guess in your instance, itā€™s likely referring to ā€œBench Markā€ the numbers either being the elevation, or the name of the survey monument.

View attachment 1880139

In this case itā€™s a triangulation survey marker located at the top of a mountain.
Looks like the 5684 is the elevation since the contour lines downslope show 5000 and 4500.
Jon 8-) :cat: :occasion14: :headbang:
 

Gare

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What about Gold Mine and Silver Mine ?
 

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