trap. And if the rat that we catch is not the one that we wanted, we set
it again.

"Precisely. That was the method.

"My housemaid had absconded at the time of the murder; she was evidently
an accomplice of the murderer. My cook had left on the same day, having
conceived a not unnatural horror of the house. Since then I had made
shift with a charwoman. But I should want a housemaid and a cook, and
if I acted judiciously in the matter of references, I might get the sort
of persons who would help my plans. For there are female rats as well as
male.

"But there were certain preliminary measures to be taken. My physical
condition had to be attended to. As a young man I was a first-class
athlete, and even now I was strong and exceedingly active. But I must
get into training and brush up my wrestling and boxing. Then I must fit
up some burglar alarms, lay in a few little necessaries and provide
myself with a suitable appliance for dealing with the 'catch.'

"This latter I proceeded with at once. To the end of a rod of rhinoceros
horn about two feet long I affixed a knob of lead weighing two pounds. I
covered the knob with a thickish layer of plaited horsehair, and over
this fastened a covering of stout leather; and when I had fitted it with
a wrist-strap it looked a really serviceable tool. Its purpose is
obvious. It was an improved form of that very crude appliance, the
sand-bag, which footpads use to produce concussion of the brain without
fracturing the skull. I may describe it as a concussor.

"The preliminary measures were proceeding steadily. I had put in a