The wall was too high to scale, and for a moment it looked as though our journey had been in vain.

But Betty's keen wits came to our rescue.
When George and I had examined the gates and had almost despaired of opening them, Betty undertook an inspection of her own, and presently called our attention to a hole, perhaps four inches in diameter, in each gate, which was hidden by round curtains of wood hung within, so completely closing up the holes as to make them invisible save on close examination.

She suggested that we pass the trace chain through one hole, draw it out through the other, hitch the horses to the two ends, and pull down the wall if the gates refused to give way.
Her plan was so good that the horses soon opened the gate, though it required a strong pull from all four of them to do it.

Betty and I were the first to enter, George following close at our heels.

The two drivers, who had taken the horses back to the coach, hitched them to a tree and soon followed us, bringing the long leather reins to be used as climbing ropes if necessary.
Hardly had we entered the gate till we saw a starlike gleam of light in a window of a room in the third story of the tower, as Lilly had predicted.
While I was convinced that the light came through a hole in the curtain rather than from a star held by Raphael to guide us, still my scepticism was rapidly turning to awe.
We were speaking of the light when two great dogs came bounding out of the darkness and attacked us.