after you brought us the will, in
fact. Jervis has been through the registers and has ascertained that no
interment under the name of John Bellingham has taken place since the
disappearance; which was just what we expected. He has also discovered
that some other person has been making similar inquiries; which, again,
is what we expected."

"And your own investigations?"

"Have given negative results for the most part. I found Doctor Norbury,
at the British Museum, very friendly and helpful; so friendly, in fact,
that I am thinking whether I may not be able to enlist his help in
certain private researches of my own, with reference to the changes
effected by time in the physical properties of certain substances."

"Oh; you haven't told me about that," said Jervis.

"No: I haven't really commenced to plan my experiments yet, and they
will probably lead to nothing when I do. It occurred to me that,
possibly, in the course of time, certain molecular changes might take
place in substances such as wood, bone, pottery, stucco, and other
common materials, and that these changes might alter their power of
conducting or transmitting molecular vibrations. Now, if this should
turn out to be the case, it would be a fact of considerable importance,
medico-legal and otherwise; for it would be possible to determine
approximately the age of any object of known composition by testing its
reactions to electricity, heat, light and other molecular vibrations. I
thought of seeking Doctor Norbury's assistance because he can furnish me
with materials for experiment of such great age that the reactions, if
any, should be extremely easy to demonstrate. But to return to our case.
I learned from him that John Bellingham had certain friends in
Paris--collectors and museum officials--whom he was in the habit of
visiting for the purpose of study and exchange of specimens. I have
made inquiries of all of these, and none of them had seen him during his
last visit. In fact, I have not yet discovered anyone who had seen
Bellingham in Paris on this occasion. So his visit there remains a
mystery for the present."

"It doesn't seem to be of much importance, since he undoubtedly came
back," I remarked; but to this Thorndyke demurred.

"It is impossible to estimate the importance of the unknown," said he.

"Well, how does the matter stand," asked Jervis, "on the evidence that
we have? John Bellingham disappeared on a certain date. Is there
anything to