终于知道宝贝简是被困在墙内，大家都很激动。米格尔告诉大家这所房子的奇特之处和这堵墙的玄机，大家不顾彻夜未眠的疲惫思考进入墙内部的办法……
For a time the three stood regarding one another with startled eyes.Then Arthur gasped："Great heaven！what fools we've been.""Come！"cried Patsy."The nursery."They rushed down the corridors to the staircase and thencea into the court.The door of the nursery stood ajar and Arthur ？rst entered and lighted a lamp.
The light fell full upon the face of a man seated in a low rocking chair and holding a half smoked cigarette in his mouth.He was fast asleep.It was old Miguel，the ranchero.
Arthur shook his shoulder，savagelyb，and the manwakened and rubbed his eyes.Then，seeing who had disturbed him，he quickly rose and made his characteristic low，sweeping bow.
"What are you doing here ？"demanded Weldon，angryand suspicious.
"I am look for Mees Jane，"returned the old man calmly."In your sleep？Come，get out of here.""Wait a minute，Arthur，"said Beth，reading Miguel's face."He knows something."Arthur looked at the man critically，reflecting that theremust be a reason for his presence in the nursery.Miguel had been fond of baby Jane.Was he merely disconsolate over her loss，or—did he really "know something"？
"Miguel once told me，"said Patsy，speaking slowly，"that he used to live in this house，in Cristoval's time，and knows it thoroughly."The old man bowed.
"I theenk，"said he，"perhaps we ？nd Mees Jane here—not somewhere else.""Why do you think that，Miguel？"It was Patsy who questioned him.He mused a bit before replying.
"The old se？or—the father of my Se？or Cristoval—wasstrange mans，"said he."He make thees house a funny way.Come；I show you."He led the way to the little room adjoining，the one Inez had occupied.In one corner of the ？oor was a square hole，with steps leading down to a sort of blind pocket.Holding a lamp in one hand Miguel descended the steps and pushedagainst a block of adobe that formed part of the outer wall.It swung inward，disclosing a cavitya about four feet in width and fully six feet high.The interior could be plainly seen from the room，by stooping close to the ？oor.There were shelves in the cavity and upon one of them stood a jar of milk.
"Oh，"cried Patsy，clasping her hands together."I toldyou the wall was hollow！"Arthur followed Miguel down the steps.He took the lamp and examined the little room.All the walls that formed it seemed solid.
Miguel was holding the block that served as a door.He released his hold，when Arthur had again ascended，and the block swung back into place.
As they returned to the nursery，Weldon asked：
"Do you know of any other rooms in the wall，Miguel？"The man shook his head，uncertainly.
"I know there be other rooms in thees wall，"said he，"for Se？or Cristoval have told me so.Hees father make the places to keep things safe from robbers—perhaps to hide from others，too.But where such places are ees the secret of the Cristovals.The room I show you ees all I know about.I thought that was secret，too；but no；the New York nurse tell Inez of that room，an'Inez she keep Mees Jane's milk there，to be cool.""Mildred told of the room！"exclaimed Arthur in astonishment.
"Yes，"said Beth，"she used to visit this house as a girl，when Cristoval lived here，and she must have known some of the secret rooms.""Ah，that ees what I theenk，"agreed old Miguel."Thereees more room in thees wall；that I know.If thees Mildreed know one room，she may know more.So I theenk she and Inez have go into some room of the wall an'take Mees Jane with them.Some way，they cannot get out again.""Exactly！"cried Patsy triumphantly."They are somewherein that wall，imprisoned，and the major really heard the baby cry.""But—Miguel，Miguel！"pleaded Arthur，earnestly，"can't you remember how the wall opens？Think！Think carefully.""I do theenk，Meest Weld；I theenk till I go sleep，an'
you ？nd me here."
"Now，let's do some thinking ourselves，"suggested Beth."The opening that leads into the wall must be from this very room.Miguel thinks so，too，and that's why he came here.Let us examine the wall."They undertook to do this，holding the lamps close to theadobe blocks and inspecting every crack.The cementa used in joining the blocks had crumbledb away at the outer edges in almost every instance，and it was impossible to tell if any block was removable or not.Miguel or Arthur pushed hard against every block in the room，from those nearest the ？oor to those far above their heads；but not one yielded a hair's breadth.
"Suppose we go outside，"said Patsy."Perhaps there issome window，or gratingc，that will give us a clue."So they took old Miguel's lantern and went into the garden where they could view the outer side of the wall.A tangle of climbing vines grew against the wing，but there was no window or other opening on the first floor.Above，on the second ？oor，were two windows，one of which admitted lightand air to the blue room.
"How about the other window？"asked Beth.
"That，"said Arthur，"must be in an unused room at the end of the corridor.We have never furnished it.""I think it might be well to examine that room，"suggested Patsy.
So they reentered the house and，followed by Miguel，ascended to the second ？oor.The door of the library was ajar and those seated there，seeing Arthur and the girls pass，came trooping out to ask what they were doing.
Patsy brie？y explained the new theory they had conceived to account for the disappearance of baby and the two nurses，and the idea was so startling that all became eager to join in the investigation.
They invaded the vacant room in a body，several of themen carrying lamps.It was in size and shape a duplicatea of the blue room，with its one window deeply embedded inb the wall，the surface of the embrasurec being covered with heavy redwood planks.