bubble level wood and brass of the 18 th century 30 cmx6, 5cmx3cm weight of 379 grams
A bubble level is an element of a measuring instrument designed to indicate whether a surface is the angle of reference. For example the horizontal, vertical and 45 ° are generally offered on the rule of the Mason.
Schematic principle of a bubble level vial. The curvature is exaggerated. The instrument contains in a small window at least a transparent ring vial and that is only partially filled with a colorful liquid, usually yellow, most often of ethanol (because of its low freezing point), in which an air bubble is trapped. Two lines indicate the position where should be the bubble to match the level. The curvature of the tube allows the pitch of the bubble between his bearings; Indeed, if the tube was cylindrical, timing would be impossible, the bubble cannot be positioned at one end without being able to isolate it in the Middle, impractical theoretical position.
Two basic orthogonal bubble levels will thus define a horizontal (use in geodesy, see inclinometer).
Sometimes called nivelle. There are also levels of the vial is a portion of a sphere to quickly align a vertical component equivalent to the wire lead. We call them level when they are solidary a foot, an instrument or a device.
The bubble level would be the invention of the physicist and french writer Melchisedech Thévenot (1620-1692) to 16601. A first water level was described in 1573 by a pole. In 1661, a french manufactured a level by enclosing an air bubble in a glass tube. In 1798, a Danish advocates to bend the tube slightly so that the bubble shows clearly the highest point. level-d-water-2. JPG level-d-water-4. JPGC' is the level-d-water-3. Jpg19eme what happened to the current level of water putting the elders in the closet. Today levels are more wood which makes them safer and they are unbreakable, what would be left to prove! This level in the 18th century picture is in perfect working order.
In the 21st century the level becomes laser, it is orientable and calculates the angles. The laser allows to see the line on the opposite wall.