@john-nolton Ballou and Steen is a great book for self study. Pages 3 - 120 on plane trig and pages 123 - 172 on spherical trig, no trig tables, but ...

@john-nolton I may have, John. When I was teaching, I loaned many of my old books to other teachers and some never found their way back to me. The Ba...

@geeoddmike Vincenty is one of my heroes, along with Oscar Adams, Rod Deakin, and Elon Musk. Speaking of Dr. Deakin, this paper of his provides an e...

@geeoddmike My reference is Plane and Spherical Trigonometry by Ballou and Steen, 1943, bought in a used book store for $1.95 sometime in the late 19...

@nate-the-surveyor Sound analysis. I've had a lemon or two among new vehicles, but I've never had a loser among the used ones. I like buying used.

@bill93 Does Uranus have an East Star?

@nate-the-surveyor Now, Nate, you know that it can go either way and you have to do good math to help decide. Either way, you're paying now for servi...

@hakeyy Sorry for the delay. I've been off forecasting covid-19 for North Carolina (scary as hell!) creating polyconic projections for Pittsburgh (am...

@bill93 Education has changed. It's all internet look-up now.

This is the nasty one from spherical trig. The problem is that the azimuth changes continuously along the course. The departure azimuth is sort of nor...

@hi-staker I'm not sure what's misspelled. Truewerk seems like a coined term, recent maybe. Werk is spelled correctly in German. It would be nice to ...

This seems to be the area in 1944, kind of the upper left-hand corner of the sheet:?ÿ/p> Hard to know how things look today and there are lots of ass...

@bill93 I took a bit of a different approach and calculated the distance and grid azimuth from the origin to R336/16, roughly 4.4 miles and 43 degrees...

Page 14 (page 20 in pdf reader) of the report gives the geographic coordinates of the grid origin of the 1925 system. It's a fascinating read, filled ...

Pages 2 and 12 of NC law address this. I haven't followed the progression for several years, but I think the current version is much watered down from...