Scale (measurement)

A scale is both a device used for measurement of weights, and a series of ratios against which different measurements can be compared. The latter need not always be a linear ratio, and is often logarithmic.

A draughtsman's scale refers to a ruler-like device, often with a triangular cross-section, that permits him to represent items in the same relative dimensions.

The scale of a map or enlarged or reduced model indicates the ratio between the distances on the map or model and the corresponding distances in reality or the original. E.g. a map of scale 1:50,000 shows a distance of 1 km as 2 cm, and a model on a scale 1:25 of a building with a height of 30 m has a height of 1.20 m. In model railways a number of standard scales are indicated by letters such as "G", "O", "HO", "N" and "Z".

Scales with special uses are often named after the person who invented them.

• The Richter Scale, the Mercali Scale[?], the Rossi-Forel Scale[?] and the Omori[?] are all used to measure the intensity of earthquakes.
• The Beaufort scale is used to measure wind force.
• The Goldberg scale[?] measures mania and depression.
• The Scoville Scale[?] measures the hotness of peppers

Add more examples here... A history of the measuring scale would be good too