another part of the laboratory, and presently returned
with two objects, one oblong and shallow, the other deep and square,
which on being set down before Mr. Tertius proved to be glass boxes,
wonderfully and delicately made, with removable lids that fitted into
perfectly adjusted grooves.

"There, my dear fellow," he said. "Presently I will deposit the glass in
that, and the sandwich in this. Then I shall adjust and seal the lids in
such a fashion that no air can enter these little chambers. Then through
those tiny orifices I shall extract whatever air is in them--to the most
infinitesimal remnant of it. Then I shall seal those orifices--and there
you are. Whoever wants to see that sandwich or that glass will find both
a year hence--ten years hence--a century hence!--in precisely the same
condition in which we now see them. And that reminds me," he continued,
as he turned away to his desk and picked up his pipe, "that reminds me,
Tertius--what are you going to do about these things being seen?
They'll have to be seen, you know. Have you thought of the police--the
detectives?"

"I have certainly thought of both," replied Mr. Tertius. "But--I think
not yet, in either case. I think one had better await the result of the
inquest. Something may come out, you know."

"Coroners and juries," observed the Professor oracularly, "are good at
finding the obvious. Whether they get at the mysteries and the
secrets----"

"Just so--just so!" said Mr. Tertius. "I quite apprehend you. All the
same, I think we will see what is put before the coroner. Now, what
point suggests itself to you, Cox-Raythwaite?"

"One in particular," answered the Professor. "Whatever medical evidence
is called ought to show without reasonable doubt what time Herapath
actually met his death."

"Quite so," said Mr. Tertius gravely. "If that's once established----"

"Then, of course, your own investigation, or suggestion, or theory about
that sandwich will be vastly simplified," replied the Professor.
"Meanwhile, you will no doubt take some means of observing--eh?"

"I shall use every means to observe," said Mr. Tertius with a significant
smile, which was almost a wink. "Of that you may be--dead certain!"

Then he left Professor Cox-Raythwaite to hermetically seal up the glass
and the sandwich, and quitting the house, walked slowly back to Portman
Square. As he turned out of Oxford Street into Orchard Street the
newsboys suddenly came rushing along wit