This fort had once been a summer-house, but it had long since been disused, and would, no doubt, have fallen into decay, had not the children hit upon the idea of making it the scene of their pitched battles, and had so propped it up and strengthened it that it was impossible to take except by surprise.

The door had been nailed up and so had the window, and entrance could only be effected by scrambling up on the flat roof, and dropping through a hole which had been made there for that purpose. Even that hole could be closed by a hatch in time of need, and the besieged could lie snugly inside and listen to the heavy firing without, secure in the knowledge that as long as he chose to remain there none of the besiegers could touch him. But then his flag would be in danger; and by their rules of warfare, if the flag were captured or shot down, the fort was held to have capitulated.

For more than a week before Hal's return from school the others had been busy getting the ammunition ready; they had dug up a quantity of sand from the bed of the stream, which, when mixed with a little clay and moistened with water, represented cannon-balls. As, however, they had no cannon, these balls had to be thrown by hand; and as they scattered when they struck, they appeared more formidable than they really were. But still one had been known to bring down the flag, and so win the day for the besiegers.

The fort was mainly defended with a catapult loaded with mud pellets, shot being strictly forbidden as too dangerous. To protect them the besiegers wore a kind of helmet, which, though it gave them a somewhat ludicrous appearance, saved them from many a nasty blow. These helmets were neither more nor less than fine wire-gauze dish-covers, which they tied across their faces and fastened at the back of their heads. But the holder of the fort had to rely chiefly upon capture to win a victory, and when his enemies approached too closely, a bold rush often resulted in one of them being made prisoner. But, of course, even a brief absence from the fort left the flag undefended, and there was always a chance that, while one of the attackers was being pursued, some of the others might steal up and succeed in going off with the flag.

So it will be easily understood that courage and skill, combined with a spirit that was bold and yet not too rash, were required to hold the fort. And as none of them possessed these qualities to the same extent as Hal, it followed that none of them held the fort as well as he did, or made such a good fight of it.

Superintended by Drusie, they all worked very busily at the ammunition, and as they kneaded cannon-balls and pellets they laid out a plan of attack for the following Tuesday. Jim was of the opinion that they never took enough advantage of the shelter afforded by the thick and almost impenetrable bushes that grew on one side of the fort, and he proposed that while two of them made an attack in the open air, he or Drusie should lie concealed, and if Hal could be drawn out in pursuit they might get a chance of slipping in during his absence.

"He may have brought back some new dodges," said Drusie hopefully. "I wonder if he has ever played a game of this sort at school? Do you think he has, Jim?"

Jim thought it was doubtful.

"I believe they always play cricket in the summer term," he said. "But this will be a splendid change for him."

"I hope it will," said Drusie, with a sigh. "But I am simply not going to think what we shall do if, after all our trouble, Hal turns up his nose at a fight on Tuesday."