Section 2 - The Turret
The Old Hexagonal Turret is east of Old City Walls. "Up here [you] stand on the remains of the old fortifications; this turret offers a view out over the docks, the fish market, and the harbor, which it was designed to protect."
The depluralizing cannon is a container in the Old Hexagonal Turret. It is fixed in place. Understand "heavy" or "old" or "barrel" as the depluralizing cannon. The printed name is "deplural[izing] cannon".
"A heavy old [depluralizing cannon] is aimed out to sea."
The description is "Like a conventional cannon it has a mounting to allow the users to turn the gun and change its angle, to hit objects at various ranges.
It is currently unloaded, of course; but time was when this vast weapon was employed to reduce entire fleets to a single ship, and a whole crew of marines to a single man. This tactic was found so effective that the harbor was never successfully taken."
Sanity-check turning or pushing or pulling the depluralizing cannon:
say "With considerable effort, we manage to point the cannon a little more [one of]towards the open sea[or]towards the docks[or]towards the cliffs opposite[cycling]. Not that that does any good." instead.
The deep purple residue is part of the depluralizing cannon. The description is "Deplural[izing] shot is usually a very dark purple near to black, and some may have scraped off on the inside of the barrel."
The scent-description is "smoke and leather".
Instead of searching the depluralizing cannon:
say "There's nothing to see inside the old barrel except perhaps the faintest traces of a [deep purple residue]."
Sanity-check inserting something into the depluralizing cannon:
say "No doubt it would be interesting to fire [the noun] out over the marina, but it's neither possible nor wise." instead.
Sanity-check entering the depluralizing cannon:
say "Col[our]ful as it would be to climb into the cannon and fire ourselves straight out to sea, this is not a viable option. I would have tried it before now if it were." instead.
Instead of facing south in Old Hexagonal Turret:
say "That way is mostly empty air, though if [you] look south and down over the edge, there is a vertiginous view down to the bottom of the monumental staircase. Tourists and natives are climbing up and down."
The mounting is part of the depluralizing cannon. The description is "Everything is stiff and motionless now."
Instead of turning or pushing or pulling the mounting:
say "No matter what [you] do [you] won't be able to aim or fire the old cannon; which is just as well, since to do so would be a major felony under local penal code, and a war crime under international conventions."
Understand "fire [cannon]" or "load [cannon]" or "aim [cannon]" or "use [cannon]" as a mistake ("[You] haven't got the shot for this thing, and for very good reason. There may not even be any still in existence, but if there is, the Bureau will keep it under lock and key.").