In this way, metaphorically speaking, a strong lens applied to Mrs. Cadwallader’s match-making will show a play of minute causes producing what may be called thought and speech vortices to bring her the sort of food she needed.
Even with a microscope directed on a water-drop we find ourselves making interpretations which turn out to be rather coarse; for whereas under a weak lens you may seem to see a creature exhibiting an active voracity into which other smaller creatures actively play as if they were so many animated tax-pennies, a stronger lens reveals to you certain tiniest hairlets which make vortices for these victims while the swallower waits passively at his receipt of custom.
There are no more uses of "vortex" in the book.
Show samples from other sources
The tunnel ended in a whirling vortex of darkness.
Cassandra Clare -- City of Heavenly Fire
What happens is the water spray creates a vortex, kind of like a hurricane.