Explanatory notes
… work remain in this heading even if made of refractory materials (e.g., thread guides, grinding apparatus, etc., of … and crucible lids, evaporating dishes, combustion boats, cupels; mortars and pestles; spoons for acids, spatulas; … and catalysts; filter plates, tubes, candles, cones, funnels, etc.; water-baths; beakers, graduated vessels ( …