Then, by a sudden rectification of her vision, she perceived that what she saw was in reality a multitude of fountain jets rushing high towards their parent-cistern, but far-failing ere they reached it.

The roar of their onset was mingled with the despairing tumult of their defeat, and both with the deep tumble and wallowing splash of the water from the fire-engine, which grew louder and louder as the surface of the water in the reservoir sank.

The uproar ceased as suddenly as it had commenced, but the moat mirrored a thousand moons in the agitated waters which had overwhelmed its mantle of weeds.
'You see now,' said lord Herbert, rejoining her while still she gazed, 'how necessary the cistern is to the keep?
Without it, the few poor springs in the moat would but sustain it as you saw it.

From here I can fill it to the brim.' 'I see,' answered Dorothy.

'But would not a simple overflow serve, carried from the well through the wall ?' 'It would, were there no other advantages with which this mode harmonised.