… physical or chemical analysis (for example, polarimeters, refractometers, spectrometers, gas or smoke analysis … for measuring or checking viscosity, porosity, expansion, surface tension or the like; instruments and apparatus for …
Explanatory notes
… 9027.89 - - Other 9027.90 ‑ Microtomes; parts and accessories This heading includes : (1) Polarimeters . … a ray of light is rotated in passing through an optically active substance. They consist essentially of a source of … (or infra‑red) rays is directed on to a photoelectric cell. According to the density of the smoke , the passage of this …