… physical or chemical analysis (for example, polarimeters, refractometers, spectrometers, gas or smoke analysis … or checking quantities of heat, sound or light (including exposure meters); microtomes. …
Explanatory notes
… physical or chemical analysis (for example, polarimeters, refractometers, spectrometers, gas or smoke analysis … Refractometers . These are instruments for determining the refractive index of liquids or solids (one of the most …