In the thread below, John Hamilton mentions leveling to BM's that are set vertically.
I rarely use vertical marks because they are a pain, even more so if you are solo!
How did USC&GS/NGS level to these originally? Did they have a jig or something made to do this, or was it a multiple person operation to hold the level rod on a knife edge at the line, etc?
I tied one last summer where I used a hydraulic jack to set the rod on and could lower and raise the jack until I deemed the bottom of the rod to be in the correct place, got to be creative when leveling solo!
SHG
To read the rest of this thread go to www.i-boards.com/bnp/pob/messages.asp?MsgID=1395207&ThreadID=132303&IsResponse=False#1395207


More







