Voltmeter - Bakelite, Wood, Glass - circa 1900

No damage-No restoration-Original tool-
If a search engine has selected only this page, isolated from the rest of the service, click the button to access the full fanantic.fr site
INSTRUMENTATION IN BRIEF
Measuring means comparing a physical quantity (such as length, area, duration, etc.) with another of the same nature chosen as a reference (which defines the unit of measurement). The autonomous apparatus that allows this comparison is called a measuring instrument (or device) of measurement.
Since antiquity, and especially since humans began trading goods of all kinds, standard measuring units have been used: for time, this naturally involved referring to their natural environment (the rhythm of the seasons, the alternation of day and night, etc.); for distances and lengths, one often used their own morphology (foot, finger, thumb, cubit, etc.); and for mass, this was obtained with the help of rudimentary scales by simply comparing with standard objects (including cereal grains). But, no matter how many places, cultures or epochs there are, there exist just as many different measurement systems. Only in France, and until the end of the 18th century, did many units coexist, with little or no compatibility among them. The