The processes covered by this sub-class include evaporation, distillation, crystallisation, filtration, dust precipitation, gas cleaning, absorption, adsorption.
This sub-class also includes similar processes which are not concerned with, or limited to, separation (except in the case of absorption or adsorption).
The word "filtration" and related words should be interpreted as embracing straining liquids from solids.
This sub-class is intended to take only laboratory apparatus which is either applicable solely to laboratory purposes or which, by reason of its simple construction and adaptability, is such as would not be suitable for industrial use.