On Tue, 14 May 2013 19:21:08 -0400, George
wrote:

I demonstrated using a water level to someone and they were absolutely
sure that it couldn't be accurate especially since it didn't have a LASER.

If you take a hose and run it from New York to California and fill it
with water, it will NOT be level due to the roundness of the earth.

Better yet, try going from the North pole to the South pole. I can
guarantee it wont work.