The card is some hocus-pocus,--a blind, as like as not.

The only question is, how did he depart?
Ah, of course, here is a hole in the roof." With great activity, considering his bulk, he sprang up the steps and squeezed through into the garret, and immediately afterwards we heard his exulting voice proclaiming that he had found the trap-door.
"He can find something," remarked Holmes, shrugging his shoulders.

"He has occasional glimmerings of reason.

_Il n'y a pas des sots si incommodes que ceux qui ont de l'esprit!_" "You see!" said Athelney Jones, reappearing down the steps again.
"Facts are better than mere theories, after all.

My view of the case is confirmed.