Looking out from the window they saw that it was over the great water wheel, whose top was some fifteen feet below them, with the water running to waste from the inlet, which led from the reservoir higher up the valley.

Presently they heard a horse gallop up to the front of the mill, and shortly after the sound of a man’s voice raised in anger.  By this time it was getting dark.

“What’ll be the end of this, Master Rupert?  We could stand a siege for a week, but they’d hardly try that.”

“What’s that?” Rupert said.  “There’s some one at the door again.”

They came back, but all was quiet.  Listening attentively, however, they heard a creaking, as of someone silently descending the stairs.  For some time all was quiet, except that they could hear movements in the lower story of the mill.  Presently Rupert grasped Hugh’s arm.

“Do you smell anything, Hugh?”

“Yes, sir, I smell a smoke.”

“The scoundrels have set the mill on fire, Hugh.”

In another minute or two the smell became stronger, and then wreaths of smoke could be seen curling up through the crevices in the floor.

“Run through the other rooms, Hugh; let us see if there is any means of getting down.”

There were three other rooms, but on opening the shutters they found in each case a sheer descent of full forty feet to the ground, there being no outhouses whose roofs would afford them a means of descent.

“We must rush downstairs, Hugh.  It is better to be shot as we go out, than be roasted here.”

Rapidly they tore away the barrier of sacks, and Rupert put his thumb on the latch.  He withdrew it with a sharp exclamation.

“They have jammed the latch, Hugh.  That was what that fellow we heard was doing.”

The smoke was now getting very dense, and they could with difficulty breathe.  Rupert put his head out of the window.

“There is a little window just over the wheel,” he said.  “If we could get down to the next floor we might slip out of that and get in the wheel without being noticed.

“Look about, Hugh,” he exclaimed suddenly; “there must be a trapdoor somewhere for lowering the sacks.  There is a wheel hanging to the ceiling; the trap must be under that.”

In a minute the trap was found, and raised.  The smoke rushed up in a volume, and the boys looked with dismay at the dense murk below.

“It’s got to be done, Hugh.  Tie that bit of sacking, quick, over your nose and mouth, while I do the same.  Now lower yourself by your arms, and drop; it won’t be above fifteen feet.  Hold your breath, and rush straight to the window.  I heard them open it.  Now, both together now.”

The lads fell over their feet, and were in another minute at the window.  The broad top of the great wheel stretched out level with them, hiding the window from those who might have been standing below.  The wheel itself was some thirty feet in diameter, and was sunk nearly half its depth in the ground, the water running off by a deep tail race.