A complete guide to the laws of the universe

A substance in a particulate form, e.g. a polyacrylamide flocculant powder, is rapidly dissolved in a liquid, e.g. water by feeding the powder down a circular bore in a casing while the water is fed tangentially and swirled in two chambers in the casing and around the circular bore to emerge in the bore, as oppositely swirling, inwardly converging streams in the path of the powder. The diverging portion of the first stream intersects the converging portion of the second stream, which goes out of the bore with the powder dissolved therein.