It was not easy to take up the old routine and forget the air castle.

All daydreaming builds this air castle; all ambition has this as its goal.

"I should like to be the queen of something more substantial than an air castle," she replied laughingly.

This was enough to cause nearly every one to look upon it as a bubble or air castle.

Moreover, to teach school had long been her secret ambition, the solid foundation of many an air castle.

But, if you value your peace of mind, do not build too gorgeous an air castle on the foundation of this printed thing.

You are not talking airship now, Stanny; it's an air castle you have in mind.

The dreamer of the future will not dare to build an air castle without at least an option on the site.

He passes to-day in building an air castle for to-morrow, or in writing yesterday's elegy.

Peter's heart fell at this, for he had a half hope that he could yet bring himself to demolish his father's air castle.