ilator,' in accordance with the sense of the words. So I concluded
that the meaning of the whole sentence was simply this: 'The plunder is
in the ventilator, the loss is discovered, take away the booty at once;
Martin Hewitt is here, and I fear I may be watched.' There is the
reading, and our little adventure this evening is what it has led to.

"Of course, the confederate wouldn't go groping about the squares so
painfully as I have had to do. To him the reading would be simple
enough, for the order of the moves would be preconcerted. Each of the
conspirators would have, as a guide, both to reading and writing the
cypher, a drawn set of squares, numbered in the order of the moves--1
where we have the _i_, 2 where we have the _n_, 3 where we have the _v_,
and so on. With that before him, either reading or writing in this
extraordinary cryptogram would be easy and quick enough. And now for
Scotland Yard!"

IV

We learned late on the following day that Henning had not appeared at
the office. From that we assumed that he must have met his confederate
in the evening, and, finding that he had not received the message sent,
conceived that something was wrong, and made himself safe. The
confederate, Hunt, however, made his appearance early next morning, but
escaped.

What happened is best told in Plummer's words when he called on Hewitt
in the afternoon.

"I went round this morning," he said, "as I said I would last night. I
took a good man with me, and we got the dummy bonds that had been put in
Bell's box and popped 'em in the ventilator, where the real ones had
been hidden. You see, we'd got nothing _legal_ against Catherton Hunt as
yet, but if we could only grab him with those dummy bonds on him it
might help, with the other evidence we could scrape up (and especially
if we could take Henning), to sustain a charge of conspiracy to steal.
Well, he came so quick he was on us before we were quite ready. We'd got
the dummies in their place, and I was in front of the door telling my
man the likeliest corner to wait in, when suddenly up pops the lift
right in front of me, with a gentleman in it--clean-shaven. I looked at
him and he looked at me. I had a sort of distant notion that I might
have seen him before, and it's pretty certain he had something more than
a distant notion about me. 'Down again,' he says to the lift man, before
the gate was swung, 'I've forgotten something!' And down the lift went.
You'll unders