rose from the floor in corners and wall angles,
and could be shut or opened by means of lids over their upper ends.
These were more to Hewitt's mind, and he went about from one to another,
groping under the lids, and poking down into the flues with a
walking-stick. There was a wire-grating, or diaphragm, it seemed, in
each of them, two or three feet down, and we could hear the end of the
stick raking on this at each investigation. One after another of these
ventilators Hewitt examined, till he had examined them all, in outer and
inner rooms, without result; and I could see that he was disappointed.

"There must be another somewhere," he said, and hunted afresh.

But plainly he had tried them all, and now he could do no more than try
them all again, with as little result.

"It _is_ a ventilator," he said, positively. "Unless----" he broke off
thoughtfully and stood silent for a few moments. "Ah! of course!" he
resumed presently. "We'll send for the housekeeper and a candle. Which
is the nearest empty office--the nearest office to let? Is there one on
this floor?"

"I think not," Mr. Bell answered. "But there's one on the floor below,
just opposite the lift--I see the bill on the door every day as I come
up."

"We'll try that, then. I'll rake out every ventilator in this palatial
edifice before I'll call myself beaten. Come, call the housekeeper. Is
there a speaking tube? Tell him to bring a light."

The housekeeper came, wonderingly, with a watch-man's oil-lantern, and
we all went to the floor below. Opposite the lift was a glass door from
which a bill had recently been torn.

"Why, it's let!" said Mr. Bell.

"Yes, sir," assented the housekeeper. "Let a day or two ago to a Mr.
Catherton Hunt. Or, at least, a deposit was paid."

"But see--the door's not locked," Hewitt observed, pushing it open. "I
think we'll trespass on Mr. Catherton Hunt's new offices, since they
seem quite empty, and he hasn't taken possession. Come--ventilators!"

It was a small office--an outer room of moderate size, and one smaller
inner room. Hewitt at once attacked the ventilators in the larger
apartment--there were two of them--but retired disappointed from each.
There was one ventilator only in the small room. Hewitt tilted the lid,
which was at about the level of his eyes, thrust in his hand, and drew
forth a bundle of folded papers; thrust in his hand again and drew forth
another bundle; did it again, and drew forth more!

Mr. Be