Bernard Ridens posed:

> ... For those that are really good I ask them to lay out a form
>for a concrete floor or footing using only a plumb bob. ...So, if
>you have read this far, I would be interested in you response to
>the floor problem above.

Well, I hadn't intended to become drawn into this question, but as someone
who uses a plumb bob fairly regularly in my work, I couldn't let it go.
Though I don't profess to be "really good" with one.

I'm presuming the only "measuring" and/or layout device available to be the
plumb bob. I'm also presuming that one would have at least four corner
(marking) stakes and one longer center stake available.

I'd first lay out the four corner stakes in a square (using equal lengths
of the plumb line to set the four stakes, and checking the diagonals in the
same manner), plumbing each stake. I would then plumb the longer stake at
the intersection of the diagonals.

Next, I would attach the plumb line as high as feasible on the center stake
and stretch it to one of the corner stakes and mark where they intersect at
an appropriate height for the form. I would then mark where the same string
length intsersects with each of the other corner stakes. The marks on each
of the four corner stakes would, I believe, all be in a level plane.

Interesting problem, and I'm "dying" to know the correct solution.

Don McConnell
Knox County, Ohio