Had it been
stolen? And was Dexter the thief? He might have passed by the men on the
watch while they were asleep, or he might have crossed the corridor in
an unguarded interval while the men were being relieved. But how could
he have got into the bedchamber except by way of the locked study door?
He _must_ have had the key! And he _must_ have secreted it weeks before
Mrs. Eustace Macallan's death! When the nurse first arrived at Gleninch,
on the seventh of the month, her evidence declared the key of the door
of communication to be then missing.

To what conclusion did these considerations and discoveries point? Had
Miserrimus Dexter, in a moment of ungovernable agitation, unconsciously
placed the clew in my hands? Was the pivot on which turned the whole
mystery of the poisoning at Gleninch the missing key?

I went back for the third time to my desk. The one person who might be
trusted to find the answer to those questions was Mr. Playmore. I wrote
him a full and careful account of all that had happened; I begged him to
forgive and forget my ungracious reception of the advice which he had
so kindly offered to me; and I promised beforehand to do nothing without
first consulting his opinion in the new emergency which now confronted
me.

The day was fine for the time of year; and by way of getting a little
wholesome exercise after the surprises and occupations of the morning, I
took my letter to Mr. Playmore to the post.

Returning to the villa, I was informed that another visitor was waiting
to see me: a civilized visitor this time, who had given her name. My
mother-in-law--Mrs. Macallan.

CHAPTER XXXVII. AT THE BEDSIDE.

BEFORE she had uttered a word, I saw in my mother-in-law's face that she
brought bad news.

"Eustace?" I said.

She answered me by a look.

"Let me he ar it at once!" I cried. "I can bear anything but suspense."

Mrs. Macallan lifted her hand, and showed me a telegraphic dispatch
which she had hitherto kept concealed in the folds of her dress.

"I can trust your courage," she said. "There is no need, my child, to
prevaricate with you. Read that."

I read the telegram. It was sent by the chief surgeon of a
field-hospital; and it was dated from a village in the north of Spain.

"Mr. Eustace severely wounded in a skirmish by a stray shot. Not in
danger, so far. Every care taken of him. Wait for another telegram."

I turned away my face, and bore as best I might the pang that wrung me
w