sadomanone

...claim to handheld GPS coordinate? I have a survey and notes from Survey Generals office from 1905 from an old mining claim. Markers were tree's and rocks. The map shows azimuths shot from one common point to corners. This is located in north central nv. can the coordinates be convered to GPS

dougger

Yes. You have to identify at least 2 of the corners, or any 2 points. From there you have to figure out the scale and orientation, almost certainly its North.

Then using whatever coordinates they used you have to figure out how much to add or subtract to get to get you GPS north and east coordinates.

In many areas an arbitrary point to the south and west was assigned local coordinates of 10,000N and 10,000E (sometimes other coordinates just as convenient were used) . All claims were tied to it and it had the advantage of keeping all trigonometric calculations in the 1st quadrant, and avoiding negatives in the tedious hand calculations. If you can find the local arbitrary starting point the conversion will be much easier. A correction factor was often put in to tie it into the larger state and national grid.