What is a Dumpy or Automatic Level
Let us look at the history of surveying levels. Since the Dumpy level was invented in early 1700's it has been considered the standard, that was up until around the 1830's when the transit level was invented. Recently the level has changed faster than you can keep up with it, but through all this the Dumpy level has remained a reliable back up just in case the modern levels breakdown.
A dumpy level, builder's auto level, leveling instrument or automatic level is an optical instrument used in surveying and building to transfer, measure, or set horizontal levels.
The level instrument is set up on a tripod and, depending on the type, either roughly or accurately set to a leveled condition using footscrews (levelling screws). The operator looks through the eyepiece of the telescope while an assistant holds a tape measure or graduated staff vertical at the point under measurement. The instrument and staff are used to gather and/or transfer elevations (levels) during site surveys or building construction. Measurement generally starts from a benchmark with known height determined by a previous survey, or an arbitrary point with an assumed height.
The Dumpy level was a simple device that was nothing more then a small telescope with a bubble level attached to it. The newer Dumpy levels have a few more bell and whistles but are still the same basic design. Some of the drawbacks of a Dumpy level are the time it takes to set up and get level, the slightest mistake in setting it up can result in an inaccurate reading, and taking more then one measurement from different directions can be off if not set up perfectly.
A Laser Level And How It Works
A laser level is a fairly recent invention, and has changed the way surveying is being done. With a self leveling laser level you can be assured that your measurement will be as accurate as humanly possible. A laser level is a level that uses a laser light to project a line....
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