There was nothing more to be done at Grave Street. Heldon Foyle remained
in the house while Green walked to the chief divisional station, and in
an hour or two the divisional inspector with a couple of men arrived.
Then Foyle saw to a strict search of the house from top to bottom.
Nothing there was that seemed to possess any great importance as bearing
on the case. The man who had fled over the roof had used a single room,
apparently as bed- and sitting-room, so it was to this place that the
detectives devoted chief attention.
"He must have been sleeping in his clothes," grumbled Green. "He hadn't
time to dress. There's the typewriter the note was written on."
He sat down before a rickety table and, inserting a piece of paper in
the machine, slowly tapped out the alphabet, and after a brief
inspection passed the paper on to the superintendent, who scanned it
casually, and was about to throw it away when something gripped his
attention.
"This looks queer," he muttered, and held the paper up slantingly away
from the gas-jet in order to examine it by what photographers call
transmitted light.
His brows were drawn together tightly. The sheet of paper which Green
had used was an ordinary piece of writing-paper. On its rough surface
Foyle had noted a slight sheen, unusual enough to attract his
attention. Even he would not have noticed it but for the angle in which
he had happened first to look at it when he took it from Green. It might
be an accidental fault in the manufacture of the paper. Yet, trivial as
it seemed, it was unusual, and one of the chief assets in detective work
is not to let the unusual go unexplained.
"It's the same typewriter. There can be no question of that," said
Green. "You can see that the 'b' is knocked about and the 'o' is out of
line."
"That's all right," said Foyle. "I wasn't thinking of that. It looks to
me as if there's some sympathetic writing on this."
He held the paper so that the heat from the gas-jet warmed it. Every
moment he expected that the heat would bring something to light on the
paper. He gave a petulant exclamation as nothing happened, and his eyes
roved over the table whence Green had taken the paper. He believed that
he was not mistaken, that there was something written which could be
brought to light if he knew how. He knew that there were chemicals that
could be used for secret communications which could only be revealed by
the use of other chemicals--a process something akin to development in
photography. It was unlikely, if the user of the room had used some
chemical agent, that he would have thought of destroying and concealing
it. But there was nothing on the table that suggested itself to Foyle as
having been used in the connection. Keenly he scrutinised the room, his
well-manicured hand caressing his chin.
"Ah!" he exclaimed at last. He had noted a small bottle of gum arabic
standing on the cast-iron mantelpiece.
Now, gum arabic can be used for a variety of purposes, and it has the
merit of invisible ink of being made decipherable by quite a simple
process which minimises the risk of accidental disclosure. The
superintendent held the paper to the gas again for a few minutes. Then
from a corner of the room he collected a handful of dust--no difficult
process, for it was long since the place had felt the purifying
influence of a broom--and rubbed it hard on the rough surface of the
paper. A jumble of letters stood out greyly on the surface. He looked at
them hard, and Green, peeping over his shoulder, frowned.
"Cipher!" he exclaimed.
It was undoubtedly cipher, but whether a simple or abstruse one Foyle
was in no position to judge. He had an elementary knowledge of the
subject, but he had no intention of attempting to solve it by himself.
There were always experts to whom appeal could be made. A successful
detective, like a successful journalist, is a man who knows the value of
specialists--who knows where to go for the information he wants. That
meaningless jumble of letters could only be juggled into sense by an
expert. Foyle nevertheless scrutinised them closely, more as a matter of
habit than of reading anything from them. They were--
UJQW. BJNT. FJ. UJM. FJTV. UIYIQL. SK. DQUQZOKKEYJPK. ANUJ. M.Q.
NG. N. AYUQNQIX. IGZ. ANUJ. SIO. IGZ. SMPPN. RT. 12845 HGZVFSF.
"We'll let Jones have a go at that," he said. "Anything else now?"
Some one handed him the knife that had been thrown at him on the landing
and a curious leather sheath that had been picked up near the bed. From
the bottom of the sheath depended a leather tassel. Foyle looked it over
and failed to discover any manufacturer's name. He slipped the weapon
into his pocket with the mental reflection that it looked Greek. The
search went on from attic to cellar, and profuse notes were taken of
everything found, with its exact position. The elaborate trouble taken
by these men to describe minutely in writing every little thing would
have seemed absurd to any one not versed in the ways of the Criminal
Investigation Department. Yet nothing was done that was not necessary.
An error of an inch in a measurement might make all the difference when
the case came on for trial.
Foyle and Green left the house in charge of the divisional man. Already
a description had been circulated of the man they had failed to
surprise; but as neither had caught more than a glimpse of a shadowy
figure in the darkness, they had had to rely on the descriptions given
by Israels and his wife. And even if that estimable pair had really
tried honestly to give a fair description of the man--which the
detectives thought was extremely doubtful--there could be little hope
that it was accurate. If the average man tries to describe the
appearance of his most intimate friend and then asks a stranger to
identify him, he will realise how misleading such descriptions may be
even at the best of times. Yet the Criminal Investigation Department had
to work with such material as they had.
Heldon Foyle was very silent as they trudged side by side out of
Whitechapel into the silent City streets--for there are no taxicabs to
be found in the East End at such hours. The case was developing; but
though he was beginning to have a hazy glimpse into some of its
workings, there was much that remained a mystery to him. His
questionings of Israels had satisfied him that the man who had escaped
was neither Grell nor Ivan. He could not blame himself for not effecting
an arrest. Looking back over the night's events, he could not see that
he could have taken further precaution. If he had taken more men the
escape would have occurred just the same over the roofs, for he would
still have felt it his duty to question Israels. He could not have
foreseen that the ready-witted Lola was there, nor that she should have
so ingeniously given the alarm. The luck had been against him.
Nevertheless he had gained an important fact. Lola was in London and was
obviously acting in concert with Grell. It was easier to look for two
persons than one. Sooner or later he would lay hands on them and solve
the mystery of the murder. He clenched his fists resolutely as his
thoughts carried him away. Meanwhile there was the cipher. If that could
be de-coded it might be valuable.
Green's voice broke in upon his thoughts.
"We didn't find anything bearing on Waverley."
"Waverley?" repeated Foyle. "Oh yes, I had almost forgotten him."
For an hour after they had reached Scotland Yard the superintendent
laboured at his desk, collecting reports and writing fresh chapters in
the book which held all the facts in relation to the crime, so far as
he knew them. He slipped the result of his labours at last in an
envelope and left them over to be dealt with by the inspector in charge
of the Registry, which is a department that serves as official memory to
Scotland Yard.
"That is all right," he said, and stretched himself.
Some one knocked at the door. The handle turned and an erect man with
his right arm carried in a black silk handkerchief improvised into a
sling entered the room. It was Detective-Inspector Waverley.