At those depths, the air becomes too dense and humid to breathe. Various creatures inhabit this region, and no-one has reached firm ground, even with air suits and floaters. I can't believe Habstad would talk this way around a lady. He must be really aggravated. Not marshal Stuhan.
Every city has one.
He is the chief maintainer of law. Seeing as Tibid is one of the lowest cities in the Emperor's reign, to be thrown off would be very bad. Paramount to death. There is probably nothing but sea and uninhabited land below. Another derivative of turpin, the gas used in the gaslamps throughout Meritech's jurisdiction.