e
detectives. 'He sold me two or three stones once or twice, I think; but
we are both single men, and we have often dined together. Last night he
dined with me. He had that afternoon received a very fine consignment of
Brazilian diamonds, as he told me, and knowing how beset I am with
callers at my business place, he had brought the stones with him,
hoping, perhaps, to do a bit of trade over the nuts and wine.

"'I bought L25,000 worth of him,' added the jeweller, as if he were
speaking of so many farthings, 'and gave him a cheque across the dinner
table for that amount. I think we were both pleased with our bargain,
and we had a final bottle of '48 port over it together. Mr. Knopf left
me at about 9.30, for he knows I go very early to bed, and I took my new
stock upstairs with me, and locked it up in the safe. I certainly heard
nothing of the noise in the mews last night. I sleep on the second
floor, in the front of the house, and this is the first I have heard of
poor Mr. Knopf's loss--'

"At this point of his narrative Mr. Shipman very suddenly paused, and
his face became very pale. With a hasty word of excuse he
unceremoniously left the room, and the detective heard him running
quickly upstairs.

"Less than two minutes later Mr. Shipman returned. There was no need for
him to speak; both the detective and the inspector guessed the truth in
a moment by the look upon his face.

"'The diamonds!' he gasped. 'I have been robbed.'"

CHAPTER V

A NIGHT'S ADVENTURE

"Now I must tell you," continued the man in the corner, "that after I
had read the account of the double robbery, which appeared in the early
afternoon papers, I set to work and had a good think--yes!" he added
with a smile, noting Polly's look at the bit of string, on which he was
still at work, "yes! aided by this small adjunct to continued thought--I
made notes as to how I should proceed to discover the clever thief, who
had carried off a small fortune in a single night. Of course, my methods
are not those of a London detective; he has his own way of going to
work. The one who was conducting this case questioned the unfortunate
jeweller very closely about his servants and his household generally.

"'I have three servants,' explained Mr. Shipman, two of whom have been
with me for many years; one, the housemaid, is a fairly new comer--she
has been here about six months. She came recommended by a friend, and
bore an excellent character. She and