Calibration n. The process of estimating the caliber a tube, as of a thermometer tube, in order to graduate it to a scale of degrees; also, more generally, the determination of the true value of the spaces in any graduated instrument.
... neutral solution of silver nitrate.1 An alternating current of one ampere is defined to be one which produces the same heat in a second in a wire as the unit continuous current defined as above to be one ampere. These definitions provide a basis on which the calibration of amperemeters can be conducted. Amperemeters may then be classified according to the physical principle on which they are constructed. An electric current in a conductor is recognized by its ability (a) to create heat in a wire through which it passes, ... — Project Gutenberg Encyclopedia