The blue scarab
handsome morocco case with an engraved gold plate.
I pounced on the case and, pressing the catch, raised the lid; and
though I had expected no less, it was with something like a shock of
surprise that I looked on the glittering row and the dazzling cluster
of steely-blue diamonds.
As I closed the casket and deposited it in the green canvas case,
Thorndyke, after a single glance at the treasure and another along the
path, crammed the towel into the hole and began to sweep the loose
earth in on top of it. The approaching stranger was for the moment
hidden from us by a bend of the path and a near clump of bushes, and
Thorndyke was evidently working to hide all traces before he should
appear. Having filled the hole, he carefully replaced the sod of turf
and then, moving over to the little bare patch from whence the turf
had been removed, he began swiftly to dig it up.
“There,” said he, flinging on the path a worm which he had just
disinterred, “that will explain our activities. You had better
continue the excavation with your pocket-knife, and then proceed to
the capture of the leviathans. I must run up to the police station and
you must keep possession of this pitch. Don’t move away from here on
any account until I come back or send somebody to relieve you. I will
hand you over the float; you’ll want that.” With a malicious smile he
dropped the gaudy monstrosity on the path and having wiped the spatula
and replaced it in the case, picked up the latter and moved away
towards Putney.
At this moment the stranger reappeared, walking as if for a wager, and
I began to peck up the earth with my pocket-knife.
As the man approached he slowed down by degrees until he came up at
something like a saunter. He was followed at a little distance by
Thorndyke, who had turned as if he had changed his mind, and now
passed me with the remark that “Perhaps Hammersmith would be better.”
The stranger cast a suspicious glance at him and then turned his
attention to me.
“Lookin’ for worms?” he inquired, halting and surveying me
inquisitively.
I replied by picking one up (with secret distaste) and holding it
aloft, and he continued, looking wistfully at Thorndyke’s retreating
figure:
“Your pal seems to have had enough.”
“He hadn’t got a rod,” said I; “but he’ll be back presently.”
“Ah!” said he, looking steadily over my shoulder in the direction of
the willow. “Well, you won’t do any good here. The place where they
rises is a quarter of a mile farther down--just round the bend there.
That’s a prime pitch. You just come along with me and I’ll show you.”
“I must stay here until my friend comes back,” said I. “But I’ll tell
him what you say.”
With this I seated myself stolidly on the bank and, having flung the
baited hook into the stream, sat and glared fixedly at the
preposterous float. My acquaintance fidgeted about me uneasily,
endeavouring from time to time to lure me away to the “prime pitch”
round the bend. And so the time dragged on until three-quarters of an
hour had passed.
Suddenly I observed two taxicabs crossing the bridge, followed by
three cyclists. A minute or two later Thorndyke reappeared,
accompanied by two other men, and then the cyclists came into view,
approaching at a rapid pace.
“Seems to be a regular procession,” my friend remarked, viewing the
new arrivals with evident uneasiness. As he spoke, one of the cyclists
halted and dismounted to examine his tyre, while the other two
approached and shot past us. Then they, too, halted and dismounted,
and having deposited their machines in the ditch, came back towards
us. By this time I was able--with a good deal of surprise--to identify
Thorndyke’s two companions as Inspector Badger and Superintendent
Miller. Perhaps my acquaintance also recognized them, or possibly the
proceedings of the third cyclist--who had also laid down his machine
and was approaching on foot--disturbed him. At any rate he glanced
quickly from the one group to the other, and, selecting the smaller
one, sprang suddenly between the two cyclists and sped away along the
path like a hare.
In a moment there was a wild stampede. The three cyclists, remounting
their machines, pedalled furiously after the fugitive, followed by
Badger and Miller on foot. Then the fugitive, the cyclists, and
finally the two officers disappeared round the bend of the path.
“How did you know that he was the man?” I asked, when my colleague and
I were left alone.
“I didn’t, though I had pretty strong grounds for suspicion. But I
merely brought the police to set a watch on the place and arrange an
ambush. Their encircling movement was just an experimental bluff; they
might have been chary of arresting the fellow if he hadn’t taken
fright and bolted. We have been fortunate all round, for, by a lucky
chance, Badger and Miller were at Chiswick making enquiries and I was
able to telephone to them to meet me at the bridge.”
At this moment the procession reappeared, advancing briskly; and my
late adviser marched at the centre securely handcuffed. As he was
conducted past me he glared savagely and made some impolite references
to a “blooming nark.”
“You can take him in one of the taxis,” said Miller, “and put your
bicycles on top.” Then, as the procession moved on towards the bridge
he turned to Thorndyke. “I suppose he’s the right man, Doctor, but he
hasn’t got any of the stuff on him.”
“Of course he hasn’t,” said Thorndyke.
“Well, do you know where it is?”
Thorndyke opened his case and taking out the casket, handed it to the
Superintendent. “I shall want a receipt for it,” said he.
Miller opened the casket, and at the sight of the glittering jewels
both the detectives uttered an exclamation of amazement, and the
Superintendent demanded: “Where did you get this, sir?”
“I dug it up at the foot of that willow.”
“But how did you know it was there?”
“I didn’t,” replied Thorndyke; “but I thought I might as well look,
you know,” and he bestowed a smile of exasperating blandness on the
astonished officer.
The two detectives gazed at Thorndyke, then they looked at one another
and then they looked at me; and Badger observed, with profound
conviction, that it was a “knock-out.” “I believe the doctor keeps a
tame clairvoyant,” he added.
“And may I take it, sir,” said Miller, “that you can establish a
_prima facie_ case against this man, so that we can get a remand until
Mr. Montague is well enough to identify him?”
“You may,” Thorndyke replied. “Let me know when and where he is to be
charged and I will attend and give evidence.”
On this Miller wrote out a receipt for the jewels and the two officers
hurried off to their taxicab, leaving us, as Badger put it, “to our
fishing.”
As soon as they were out of sight, Thorndyke opened his case and mixed
another bowlful of plaster. “We want two more casts,” said he; “one of
the right foot of the man who buried the jewels and one of the right
foot of the prisoner. They are obviously identical, as you can see by
the arrangement of the nails and the shape of the new patch on the
sole. I shall put the casts in evidence and compare them with the
prisoner’s right boot.”
I understood now why Thorndyke had walked away towards Putney and then
returned in rear of the stranger. He had suspected the man and had
wanted to get a look at his footprints. But there was a good deal in
this case that I did not understand at all.
“There,” said Thorndyke, as he deposited the casts, each with its
pencilled identification, in his canvas case, “that is the end of the
Blue Diamond Mystery.”
“I beg your pardon,” said I, “but it isn’t. I want a full explanation.
It is evident that from the house at Brentford you made a bee line to
that willow. You knew then pretty exactly where the necklace was
hidden. For all I know, you may have had that knowledge when we left
Scotland Yard.”
“As a matter of fact, I had,” he replied. “I went to Brentford
principally to verify the ownership of the wallet and the bag.”
“But what was it that directed you with such certainty to the
Hammersmith towing-path?”
It was then that he made the observation that I have quoted at the
beginning of this narrative.
“In this case,” he continued, “a curious fact, well known to
naturalists, acquired vital evidential importance. It associated a
bag, found in one locality, with another apparently unrelated
locality. It was the link that joined up the two ends of a broken
chain. I offered that fact to Inspector Badger, who, lacking the
knowledge wherewith to interpret it, rejected it with scorn.”
“I remember that you gave him the name of that little shell that
dropped out of the handful of grass.”
“Exactly,” said Thorndyke. “That was the crucial fact. It told us
where the handful of grass had been gathered.”
“I can’t imagine how,” said I. “Surely you find shells all over the
country?”
“That is, in general, quite true,” he replied, “but _Clausilia
biplicata_ is one of the rare exceptions. There are four British
species of these queer little univalves (which are so named from the
little spring door with which the entrance of the shell is furnished);
_Clausilia laminata_, _Rolphii_, _rugosa_ and _biplicata_. The first
three species have what we may call a normal distribution, whereas the
distribution of _biplicata_ is abnormal. This seems to be a dying
species. It is in process of becoming extinct in this island. But when
a species of animal or plant becomes extinct, it does not fade away
evenly over the whole of its _habitat_, but it disappears in patches,
which gradually extend, leaving, as it were, islands of survival. This
is what has happened to _Clausilia biplicata_. It has disappeared from
this country with the exception of two localities; one of these is in
Wiltshire, and the other is the right bank of the Thames at
Hammersmith. And this latter locality is extraordinarily restricted.
Walk down a few hundred yards towards Putney, and you have walked out
of its domain; walk up a few hundred yards towards the bridge, and
again you have walked out of its territory. Yet within that little
area it is fairly plentiful. If you know where to look--it lives on
the bark or at the roots of willow trees--you can usually find one or
two specimens. Thus, you see, the presence of that shell associated
the handful of grass with a certain willow tree, and that willow was
either in Wiltshire or by the Hammersmith towing-path. But there was
nothing otherwise to connect it with Wiltshire, whereas there was
something to connect it with Hammersmith. Let us for a moment dismiss
the shell and consider the other suggestions offered by the bag and
stick.
“The bag, as you saw, contained traces of two very different persons.
One was apparently a middle-class man, probably middle-aged or
elderly, cleanly, careful as to his appearance and of orderly habits;
the other, uncleanly, slovenly and apparently a professional criminal.
The bag itself seemed to appertain to the former person. It was an
expensive bag and showed signs of years of careful use. This, and the
circumstances in which it was found, led us to suspect that it was a
stolen bag. Now, we knew that the contents of a bag had been stolen.
We knew that an empty bag had been picked up on the line between
Barnes and Chiswick, and it was probable that the thief had left the
train at the latter station. The empty bag had been assumed to be Mr.
Montague’s, whereas the probabilities--as, for instance, the fact of
its having been thrown out on the line--suggested that it was the
thief’s bag, and that Mr. Montague’s had been taken away with its
contents.
“The point, then, that we had to settle when we left Scotland Yard,
was whether this apparently stolen bag had any connection with the