“But now that I think of it, it could not have been poor Silvio that injured Father.  My door was shut when I first heard the sound; and Father’s was shut when I listened at it.  When I went in, the injury had been done; so that it must have been before Silvio could possibly have got in.”  This reasoning commended itself, especially to me as a barrister, for it was proof to satisfy a jury.  It gave me a distinct pleasure to have Silvio acquitted of the crime—­possibly because he was Miss Trelawny’s cat and was loved by her.  Happy cat!  Silvio’s mistress was manifestly pleased as I said: 

“Verdict, ‘not guilty!’” Doctor Winchester after a pause observed: 

“My apologies to master Silvio on this occasion; but I am still puzzled to know why he is so keen against that mummy.  Is he the same toward the other mummies in the house?  There are, I suppose, a lot of them.  I saw three in the hall as I came in.”

“There are lots of them,” she answered.  “I sometimes don’t know whether I am in a private house or the British Museum.  But Silvio never concerns himself about any of them except that particular one.  I suppose it must be because it is of an animal, not a man or a woman.”

“Perhaps it is of a cat!” said the Doctor as he started up and went across the room to look at the mummy more closely.  “Yes,” he went on, “it is the mummy of a cat; and a very fine one, too.  If it hadn’t been a special favourite of some very special person it would never have received so much honour.  See!  A painted case and obsidian eyes—­just like a human mummy.  It is an extraordinary thing, that knowledge of kind to kind.  Here is a dead cat—­that is all; it is perhaps four or five thousand years old—­and another cat of another breed, in what is practically another world, is ready to fly at it, just as it would if it were not dead.  I should like to experiment a bit about that cat if you don’t mind, Miss Trelawny.”  She hesitated before replying: 

“Of course, do anything you may think necessary or wise; but I hope it will not be anything to hurt or worry my poor Silvio.”  The Doctor smiled as he answered: 

“Oh, Silvio would be all right:  it is the other one that my sympathies would be reserved for.”

“How do you mean?”

“Master Silvio will do the attacking; the other one will do the suffering.”

“Suffering?” There was a note of pain in her voice.  The Doctor smiled more broadly: 

“Oh, please make your mind easy as to that.  The other won’t suffer as we understand it; except perhaps in his structure and outfit.”

“What on earth do you mean?”

“Simply this, my dear young lady, that the antagonist will be a mummy cat like this one.  There are, I take it, plenty of them to be had in Museum Street.  I shall get one and place it here instead of that one—­ you won’t think that a temporary exchange will violate your Father’s instructions, I hope.  We shall then find out, to begin with, whether Silvio objects to all mummy cats, or only to this one in particular.”