It implicitly assumed a geoid that depended only on latitude. See NOS NGS 34 under Orthometric Correction.

That's pretty much the way I'd work it, but instead of doing it in square feet, if you express the area as 75 sq chains it works out nicely and the on...

I'm not absolutely sure, but I think what aviators call "MSL" these days is NAVD88 elevation.?ÿ The term MSL was in common use when NGVD29 vertical da...

My intuition says that might be good when Polaris is near elongation, but far worse than using wristwatch time when it is high or low and traveling ne...

Looks like he would have to go to near Cincinnati, Louisville, or Evansville for the nearest ones.

Each offense to require completion of a 1-semester course or a Jeff Lucas seminar in boundary law.

All of them so far. Just wait.

Some of the errors in John's description can be minimized if you set up 3 tripods with tribrachs so you have forced centering. Shoot AC, move instrume...

But I would bet that 99 out of 100 users DO assume the instrument offset has been calibrated to zero. No, it will not. That is a misstatement of you...

It gives the constant for this prism and instrument combination. That is not exactly the prism constant, but I think most people assume that the inst...