Romans built the Coliseum, Greeks the Pantheon, Egyptians the Pyramids. And, all this was accomplished without the help of modern tools or construction equipment. Granted, construction projects were measured in generations rather than months or years, but the quality of workmanship was impeccable – and accurate.

Did you ever wonder how the ancients got things straight without surveyor’s equipment or a fancy steel or wood-frame level? Fact is, they did have levels. Not as we know them today, but levels nonetheless. The kind that was used to build the Pyramids is still being used by many folks in construction today. Knowing that water finds its own level is all we need to know to fashion one of your own.

First, find a curved tube, preferably one that you can see through – although a solid tube works as well. Fill it with water and, presto, you have a level. No matter how you hold it as long as you don't let the water spill out, the water level at both ends of the tube will always be the same. Lower both ends of the tube until the water at each end is at the very mouth of the tube. The mouths at each end of the tube are at exactly the same height. From this point a pencil mark can be made at each end and a string line can be stretched creating a perfectly level reference point from which to work.

To demonstrate that your level works, hold the curved tube filled with water against a wall. Mark the exact height of the water at each end of the tube. Scribe a pencil line across the two marks. A borrowed level will verify that your improvised one did the job. And you aren't limited to a curved tube. You also can make your level out of a hose. A clear one is the easiest to use.

It doesn't make any difference how far apart the ends of the hose are, how the hose lies on the ground or how many coils, knots or curls are in it. The water at one end of the hose will be the same height as the water at the other end of the hose.

What's a level good for? Hanging a picture, installing a cabinet or building a redwood deck are examples. Even a pitched roof has to begin at some point that is level. Want to check the floor at the front of your house to see if it is the same height as the floor at the back of your house? You can't do that with a conventional level or your PDA’s “Level” app.