believing that he had not employed any accomplice, but had done the deed
alone.

How? That was the question. Ercole knew his dog well enough, and was
perfectly sure that if the body had been concealed anywhere within a
mile of the cottage Nino would have found it out, for the dog and his
master had quartered every foot of the ground within three days after
Marcello had been lost. It was utterly, entirely impossible that Folco,
without help, could have dragged the dead boy farther. When he had gone
on his pretended search he had not been alone; one of the men had ridden
with him, and had never lost sight of him, as Ercole easily ascertained
without seeming to ask questions. Ercole had obtained a pretty fair
knowledge of Corbario's movements on that day, and it appeared that he
had not been absent from the cottage more than half an hour at any time
before he went to look for Marcello.

"If Corbario himself had disappeared in that way," said Ercole to
himself and Nino, "it would be easy to understand. We should know that
the devil had carried him off."

But no such supernatural intervention of the infernal powers could be
supposed in Marcello's case, and Ercole racked his brains to no purpose,
and pondered mad schemes for carrying Corbario off out of Rome to a
quiet place where he would extract the truth from him, and he growled at
the impossibility of such a thing, and fell to guessing again.

In the magnificent library of the villa on the Janiculum, Folco was
guessing, too, and with no better result. But because he could not guess
right, and could get no news of Marcello, his eyes were growing hollow
and his cheeks wan.