ther room.

"What is the matter with him, doctor?" asked Mrs. Selby.

"It is, I think, a case of what is called blood-clot, which has formed
in the veins of the leg," I answered. "Part of this clot has been
detached by exertion, or possibly by rubbing, and, travelling upwards,
has become impacted in one of the pulmonary arteries."

"Is it serious?" asked the poor wife.

"Of course we must hope for the best," I said; "but it is my duty to
tell you that I do not myself think Major Selby will recover; how long
he will last depends upon the size of the clot which has got into the
artery."

"Oh, this is ridiculous," broke in Mr. Selby. "My brother has been under
the care of Sir John Bell, the ablest doctor in Dunchester, who told him
several times that he was suffering from nothing but rheumatism, and
now this gentleman starts a totally different theory, which, if it
were true, would prove Sir John to be a most careless and incompetent
person."

"I am very sorry," I answered; "I can only hope that Sir John is right
and I am wrong. So that there may be no subsequent doubt as to what I
have said, with your leave I will write down my diagnosis and give it to
you."

When this was done I returned to the patient, and Mr. Selby, taking
my diagnosis, telegraphed the substance of it to Sir John Bell for his
opinion. In due course the answer arrived from Sir John, regretting that
there was no train by which he could reach Dunchester that night,
giving the name of another doctor who was to be called in, and adding,
incautiously enough, "Dr. Therne's diagnosis is purely theoretical and
such as might be expected from an inexperienced man."

Meanwhile the unfortunate Major was dying. He remained conscious to the
last, and, in spite of everything that I could do, suffered great pain.
Amongst other things he gave an order that a _post-mortem_ examination
should be made to ascertain the cause of his death.

When Mr. Selby had read the telegram from Sir John he handed it to me,
saying, "It is only fair that you should see this."

I read it, and, having asked for and obtained a copy, awaited the
arrival of the other doctor before taking my departure. When at length
he came Major Selby was dead.

Two days later the _post-mortem_ was held. There were present at it
Sir John Bell, myself, and the third _medico_, Dr. Jeffries. It is
unnecessary to go into details, but in the issue I was proved to
be absolutely right. Had Sir John take