, quite apart
from humanitarian scruples, of appearing publicly in connection with
a murder trial. Many important witnesses in such cases have to be
practically forced into giving their evidence. They feel there is
defilement even in the shadow of the scaffold.'

Mrs Manderson tapped her lips with the envelope without quite concealing
a smile. 'You didn't think of another possibility, I suppose, Mr Trent,'
she said.

'No.' He looked puzzled.

'I mean the possibility of your having been wrong about Mr Marlowe as
well as about me. No, no; you needn't tell me that the chain of evidence
is complete. I know it is. But evidence of what? Of Mr Marlowe having
impersonated my husband that night, and having escaped by way of my
window, and built up an alibi. I have read your dispatch again and
again, Mr Trent, and I don't see that those things can be doubted.'

Trent gazed at her with narrowed eyes. He said nothing to fill the brief
pause that followed. Mrs Manderson smoothed her skirt with a preoccupied
air, as one collecting her ideas.

'I did not make any use of the facts found out by you,' she slowly said
at last, 'because it seemed to me very likely that they would be fatal
to Mr Marlowe.'

'I agree with you,' Trent remarked in a colourless tone.

'And,' pursued the lady, looking up at him with a mild reasonableness in
her eyes, 'as I knew that he was innocent I was not going to expose him
to that risk.'

There was another little pause. Trent rubbed his chin, with an
affectation of turning over the idea. Inwardly he was telling himself,
somewhat feebly, that this was very right and proper; that it was quite
feminine, and that he liked her to be feminine. It was permitted to
her--more than permitted--to set her loyal belief in the character of a
friend above the clearest demonstrations of the intellect. Nevertheless,
it chafed him. He would have had her declaration of faith a little less
positive in form. It was too irrational to say she 'knew'. In fact
(he put it to himself bluntly), it was quite unlike her. If to be
unreasonable when reason led to the unpleasant was a specially feminine
trait, and if Mrs Manderson had it, she was accustomed to wrap it up
better than any woman he had known.

'You suggest,' he said at length, 'that Marlowe constructed an alibi for
himself, by means which only a desperate man would have attempted,
to clear himself of a crime he did not commit. Did he tell he was
innocent?'

She u