the liberty to cut the carpet to mark the positions of our chairs。
In view of all these facts what must they conclude？ Simply this：
no one entered the room； did the deed； and then left it； at least
not without being observed。〃 〃But surely；〃 I ventured to suggest；
〃you do not think they will presume to question the testimony of
all of us that no one was observed。〃
〃That is all negative evidence；〃 he replied； 〃and does not
conclusively prove that another might not have observed what we
failed to detect。 However； it is all so self…evident that they
will not question it。 I know so well their methods of reasoning
that I am already prepared to refute their conclusions at every
point； without； I regret to say； being myself able to solve the
mystery； though I may say in passing that I purposely am refraining
from formulating any theory whatever until I have ascertained
everything which it is possible to learn in the matter。 In this way
I hope to avoid the error into which the detective is so prone to
fall。 Once you set up an hypothesis you unconsciously； and in spite
of yourself； accentuate unduly the importance of all data making
toward that hypothesis； while； on the other hand you either utterly
neglect； misconstrue； or fail to fully appreciate； the evidence
oppugnant to your theory。 In chemical research I gather the material
for an entire series of experiments before performing any； so that
the first few shall not； either by satisfying or discouraging me；
cause me to leave the bush half beaten。
〃Let us see how； from the officers' standpoint； the murder hypothesis
now stands。 No assassin； it will be clear to them； could have
entered or left this room unobserved。 If； therefore； a man did enter
the room and kill our friend； we； all of us； must be his accomplices。〃
This remark drew some sort of exclamatory protest from every other
person in the room save Browne。
〃Ah； that is probably the true solution；〃 said the artist with
ill…concealed disgust。
This remark and the tone in which it was uttered would have been
discourteous under any circumstances； at this particular time and in
the painful situation in which we all found ourselves it was boorish
almost beyond endurance。
There was nothing in Maitland's manner to indicate that he had heard
Browne's remark； as he quietly continued：
〃You see this cold…blooded view； the mere statement of which causes
you all to shudder； … the more so because one of our number is the
daughter of the dead man； … is not to be entertained a moment and
is only mentioned to show the logical chain which will force the
officers into the certain conviction that no assassin did enter or
leave this room。 What； then； remains of their theory？ Two
possibilities。 First； the murderer may have done the deed without
entering。 If so； it is clear that he must have made use of the
partly…opened window。 This seems so likely that they will seize
upon it with avidity。 At first they will suggest that the assassin
reached in at the window and struck his victim as he sat by it。
This； they will urge； accounts for our not finding the weapon； and
they will be so sure that this is the correct solution of the
problem that I shall probably have to point out to them its patent
absurdity。 This illustrates the danger of forming an hypothesis
from imperfect data。 Remind them that Mr。 Darrow did not sit by
the window； but eight feet three and one…half inches from it； in
almost the exact centre of the room； and their theory falls to the
ground； only to be hastily replaced； as a drowning man catches at a
straw； by a slightly varied theory。 If the victim sat that distance
from the window； they will inform us； it is clear the murderous
implement must have been thrown or shot at him by the assassin。〃
〃Indeed；〃 said Mr。 Herne； 〃though I had not thought of that theory
it seems to me so plausible； now that you mention it； that I think
the officers will show rare acumen if they adopt it。 Very properly
may they hold that some projectile might have been shot through the
partly opened window and none of us have detected the act。〃
〃Ah； yes；〃 rejoined Maitland； 〃but when I ask them where this
implement is under this assumption； and remind them of what I shall
already have told them； viz。； that Mr。 Darrow sat back to the window
as well as over eight feet from it； and sat in a chair； the solid
back of which extended； like a protecting shield； fully six inches
above the top of his head； they will find it difficult to show how；
unless projectiles travel in sharp curves or angles； a man in this
position could thus receive a wound directly beneath his chin； a
wound so slight as not to penetrate the thyroid cartilage immediately
under it。
〃The abandonment of this hypothesis will force them to relinquish
the idea that the murder was committed from without。 What then
remains？ Only the second alternative。 They must either give up
altogether the idea of murder； or have recourse to what is known as
the theory of exclusive opportunity。〃
〃Theory of exclusive opportunity；〃 repeated Gwen； as a puzzled look
overspread her countenance。 〃I … I fear I do not quite understand
what you mean。〃
〃Pardon me； Miss Darrow； for not making my meaning clearer to you；〃
said Maitland with a deferential inclination of the head。 〃The
theory of exclusive opportunity； to state it plainly in this case；
means simply this： if Mr。 Darrow were murdered； some one of us five；
we being the only ones having an opportunity to do the deed； must
be the assassin。 Whether this view be taken； or that of suicide； it
becomes of paramount importance to find the weapon。 Do you not now
see why I objected to having anyone leave the room？ If； as appears
likely from my search； the weapon is not to be found； and if； as I
feel reasonably certain； either the suicide or the murder theory be
substantiated； then； anyone who left the room before official search
was made would be held to have taken the weapon with him and disposed
of it； because his would have been the exclusive opportunity of so
doing。 Someone must have disposed of it； and no one else had a
chance to do so； that would be the way it would be stated。 But；
since no one of us has left the room； a thorough search both of it
and of our persons； must convince the officers that we； at least；
are not responsible for the fact that the weapon is not forthcoming。〃
Maitland paused and looked at Browne as if he expected him to speak；
but that gentleman only shut his square jaws the more firmly together
and held his peace； … at least in so far as words were concerned。
If looks； like actions； 〃speak louder than words；〃 this black visage
with its two points of fire made eloquent discourse。 I charged all
this display of malice to jealousy。 It is not altogether pleasant
to be placed at a disadvantage before the one being whose good
opinion one prizes above all things else； … that is to say； I have
read that such is the case。 I do not consider my own views upon
such matters expert testimony。 In all affairs of the heart my
opinions cease to have weight at exactly the point where that organ
ceases to be a pump。
Even Gwen； I think； noticed Browne's determined silence； for she
said to Maitland：
〃I am very grateful that your forethought prevented me from causing
Mr。 Browne even temporary annoyance by making him my messenger。〃
She paused a moment and then continued：
〃You were speaking of the officers' theories。 When they have
convinced themselves that no one of us has removed the weapon； what
then？〃
〃In my opinion；〃 said Maitland； 〃they will ultimately fall back upon
the suicide theory； but they must find the weapon here before they
can substantiate it； for if it be not here someone must have taken
it away and that someone could have only been the one who used it
… the assassin； in short … but here are the officers。 Let each one
of us insist upon being searched。 They can send to the station for
a woman to search you；〃 he said in an undertone to Gwen and then
added： 〃I trust you will pardon my suggesting a course which； in
your case； seems so utterly unnecessary； but； believe me； there are
urgent reasons for it which I can explain later。 If we would hope
to solve this mystery； everything depends upon absolute thoroughness
at this juncture。〃
〃I should evince but poor appreciation；〃 Gwen replied； 〃of the
ability you have already shown should I fail to follow your slightest
suggestion。 It is all I can offer you by way of thanks for the
kind interest you have taken。〃
The return of Officer Barker； accompanied by three other men； now
changed the tide of conversation。 Maitland advanced and shook hands
with one whom he introduced as Mr。 Osborne； and this gentleman in
turn introduced his brother officer； a Mr。 Allen； and ； a
special detective。
Osborne impressed me as a man of only mediocre ability； thoroughly
imbued with the idea that he is exceptionally clever。 He spoke
loudly and； I thought； a bit ostentatiously； yet withal in a manner
so frank and hearty that I could not help liking the fellow。
； on the contrary； seemed retiring almost to the point of
self…abnegation。 He said but little； apparently preferring to keep
in the background； where he could record his own observations in
his note…book without too frequent interruption。 His manner was
polished in the extreme； and so frank withal that he seemed to me
like a man of glass through whom every thought shone unhindered。
I wondered how one who seemed powerless to conceal his own emotions
should possess a detective's ability to thread his way through the
dark and hidden duplicity of crime。 When he spoke it was in a low；
velvety； and soothing voice； that fell upon the ear with an
irresistible charm。 When Osborne would make some thoughtless
remark fraught with bitterness for Gwen； such an expression of pain
would flit across 's fine face as one occasionally sees
in those highly organised and sympathetic natures； … usually found
among women if a doctor's experience may be trusted； … which catch
the throb of another's hurt； even as adjacent strings strive to
sing each other's songs。
seemed to me more priest tha