umbrella
with which he shielded himself from the storm? The fact that the
murderer carried an umbrella is proved by the discovery of a small patch
of umbrella silk which had got caught on a nail by the window. Again,
why should a man, getting from one window to another, bother about using
an umbrella for a journey of a few feet only? He would know that he
could not use it when carrying the body to the pit, for that task would
require both his hands. And what had Penreath done with the umbrella
afterwards?

"The clue of the umbrella silk, and the pool of water near the window
where the murderer placed the umbrella after getting into the room,
definitely fixed the time of the murder between eleven and 11.30 p.m.,
because the violent rainstorm on that night ceased at the latter hour.
If Penreath was the murderer, he waited until the storm ceased before
removing the body. There were no footprints outside the window where the
murderer got in, because they were obliterated by the rain. On the other
hand, the footsteps to the pit where the body was thrown were clear and
distinct, proving conclusively that no rain fell after the murderer left
the house with his burden. It seemed to me unlikely that a man after
committing a murder would coolly sit down beside his victim and wait for
the rain to cease before disposing of the body. His natural instinct
would be to hide the evidence of his crime as quickly as possible.

"These points, however, were of secondary importance, merely tending to
shake slightly what lawyers term the probability of the case against
Penreath. But a point of more importance was my discovery that the
candle-grease dropped on the carpet was of two different kinds--wax and
tallow--suggesting that two different persons were in the room on the
night of the murder. Mr. Glenthorpe did not use a candle, but a reading
lamp. Neither did Mr. Glenthorpe use the gas globe in the middle of the
room. Yet that gas tap was turned on slightly when we examined the room,
and the globe and the incandescent burner smashed. Who turned on the
tap, and who smashed the globe? Penreath is not tall enough to have
struck it with his head. Superintendent Galloway's theory was that it
might have been done by the murderer when throwing the body of his
victim over his shoulder.

"An ideal case of circumstantial evidence may be weakened, but not
destroyed, by the destruction of one or more of the collateral facts
which go to make it up.