The only thing holding up a Gothic cathedral is some mortar, gravity and a lot of math.
The french probably had reservations about dropping an uncontrolled 5-8 tons of mass into the foundation and risk destabilizing the load bearing elements of the structure. Sure, its not like dropping a 5 ton wrecking ball into the cathedral, but 1,621 gallons of water would have to go somewhere, and would pool on the stone vaults (ie: ceiling) and wash debris into main chambers.
What makes the Gothic architecture work, is the careful distribution of weight across the structure using columns and arches. The weight of the upper mass of the cathedral presses down and outward. Gothic architecture is recognizable by its signature flying buttresses, the half arches on the outside, that counter the outward pressure with their own inward force. If a major load-bearing arch were to collapse, it could trigger a chain-reaction and the loss of the cathedral.
Although the cathedral is mostly stone and can't burn... the heat of the fire might compromise the integrity of stonework causing it to break or fall apart.
good one...
