sentences:  A centuries-old researcher-mage, Rohder had discovered new geometric properties that could boost the production of plasm in cities, with the unfortunate need to completely reorder their infrastructure at prohibitive cost.Fortunately, Caraqui is a metropolis built on pontoons in the shallows of one of the world's seas, so Constantine enables him to experiment by physically moving parts of the city in concordance with his theory, which proves valid.Aiah also stumbles onto the knowledge that at periodic intervals, a small hole opens up in the Shield through which plasm-based constructs can be sent.