Mildred explained to them the manner in which she had first entered the wall, putting in action the secret method taught her as a girl by Cristoval and demonstrating the mechanism before their very eyes. They entered the lower chamber, one by one, and this time the adobe door was not closed behind them, although the light of broad day now flooded the place through the opening discovered by Runyon. This opening led into the garden and was half choked with rose vines. The series of swinging blocks had been propped back against the outer wall to insure a ready exit in case of accident.