Miss Silver continued without any change of manner.

‘Only what, Frederick?’

‘There wasn’t nothing, miss-only I thought I’d get along to the baize door and just have a look to see the coast was clear. I mean, I wouldn’t want Mr. Marsham to catch me getting out of a window.’

‘Of course you would not. So you opened the baize door?’

‘Just the least creak-not so anyone would notice.’

‘And was there anyone to notice, Frederick?’

‘Well, miss, there was and there wasn’t in a manner of speaking.’

‘Do you mean that you saw someone, but he did not see you?’

‘That’s right, miss.’

Frank Abbott took a sharp breath. Lamb sat like a rock.

Miss Silver said equably,

‘Whom did you see?’

‘Only Mr. Marsham-going into the study, miss. Lucky I wasn’t only half a minute sooner, or he might have seen me move the door.’

‘He did not see you? You are sure about that?’

‘Oh, no, miss. He was half-way in-he wasn’t looking my way.’

‘You are sure that it was Marsham you saw? Going into the study at about twenty minutes past eleven on Saturday night?’

‘Oh, yes, miss.’

Lamb’s big hand lifted, and came down with a resounding slap on his knee.

‘Then why didn’t you say so before?’

‘I-sir-’ Frederick turned an alarmed and bewildered look upon the Chief Inspector.

‘Why-didn’t-you-say-so-before?’

‘It was only Mr. Marsham, sir, going his rounds.’

Absorbing as was the sight of a purple-faced Chief Inspector and a young man who appeared to be about to burst into tears, it was at this moment that Miss Silver and Frank Abbott found their attention irresistibly diverted by the appearance-the very rapid and energetic appearance-of Professor Richardson who, having come up the terrace steps two at a time, was now rattling the handle of the glass door with one hand whilst knocking loudly with the other.

Frederick turned, Lamb turned, they all turned. Frank Abbott got up with a slight shrug and opened the door. The Professor bounded in, his square form enveloped in tweeds of a prehistoric cut, his red hair standing up wildly about the bald patch on his crown.

‘Ah,’ he said-‘that’s better! I thought the damned thing had stuck. What do you want to go locking doors for in the daytime? Never lock mine-insult to one’s neighbours. If a burglar wants to get in he will. And what are the police for anyhow? Haven’t arrested anyone yet, have you?’

Frank Abbott, his voice at its coolest, performed an introduction.

‘This is Professor Richardson, sir.’

The Professor was unwinding a large mustard-coloured scarf.

‘You keep this place too hot. Always told Whitall he. kept it too hot. No living-room should have a temperature of over sixty Fahrenheit. Have you arrested anyone yet? Because if you have, you’re probably making a mistake-and if you were thinking of arresting me, you would be making a bigger one. So I’ve come here to tell you something.’

At the Professor’s entrance Frederick had removed himself as far as he dared. He was now kneeling on the hearth and making believe to be very busy over the fire.

The Professor came round the table, flung his scarf on the ground, and thumped down into the just vacated chair.

‘Now you just listen to me!’ he said in his most sonorous tones. He appeared to be unaware of the Chief Inspector’s dominating stare. He had come there to say something, and he was going to say it. ‘I made a statement yesterday to that young fellow-me-lad. All correct, and I’m standing by every word. But I’ve got something to add to it.’ He addressed Lamb. ‘I take it you’re the Lord High Something-or-other from Scotland Yard -and that you know what’s been going on.’

Frank Abbott raised an eyebrow.

‘The Chief Inspector has seen all the statements.’ He dipped into the case before him and passed some typewritten sheets to his Chief.

‘All right-that’s what I wanted to know. Now we can get going!’ He directed himself to Lamb again. ‘If you’ll turn to the end of my statement you’ll see I said I went away at getting on for a quarter past eleven. I’d pretty well flattened Whitall out-he wouldn’t admit it of course, but he knew it all right- and there wasn’t anything to stay for. So I went out by that door to the terrace, and he fairly banged it after me and drove down the bolt. A grown man should have more control over his temper. Well, then I went round the house, picked up my autocycle-I’m not one of your plutocrats, I don’t run to a car-and went off down the drive. I hadn’t got far along the road when I remembered I had left my magnifying-glass- Whitall had it in his hand, and I hadn’t got it back from him. It was a good glass, and I wasn’t going to lose it. The temper he was in, he might have chucked it in the fire, or out of the window, or anything. So I went back.’

Everyone in the room held their breath. Lamb said,

‘If this is a confession, I must warn you-’

The Professor said, ‘Tchah!’ in a loud explosive manner.

‘I must warn you-’

‘You don’t have to! I’m not confessing anything! Do you suppose I’d be such a fool? I’m engaged on some very serious research work, and I couldn’t possibly spare the time to be arrested. Anyhow I haven’t got anything to confess, and if you’ll listen to me instead of interrupting, I can prove it. What do you suppose I’m here for? Now listen!’

Lamb nodded.

‘All right-what do you want to say?’

‘That’s more like it! Well, I came back, pushed my bike up against a tree at the top of the drive, and came round the house to the terrace. I got to the steps, and I thought, “That’s queer”. Because I told you Whitall had banged and locked the door behind me, and it was open-or, I should say, it was opening. The curtains didn’t meet, because there was a man standing between them and he was opening the door. I was two-thirds of the way up the steps by this time, but I didn’t go any farther. I thought it was damned queer. I was wondering why on earth Whitall should be opening the door at that time of night.’

‘You say it was Sir Herbert Whitall who was opening the door?’

‘I don’t say anything of the sort! I thought I told you not to interrupt! I only thought it was Whitall just long enough to get the feeling that it was queer. And then I saw it was only the butler going round making sure everything was shut up for the night-though why he should have wanted to open that damned door passes me. Didn’t trust anyone to do it properly except himself, I suppose. Always did think the man had wind in the head. So you see, you’ve only got to ask the fellow, and he can tell you he was in the study after I left, and Whitall-,’ he stopped suddenly, the blood rushing to his face, and said in a voice like an explosion, ‘Oh, good Lord!’

If he wished to strike everyone dumb, he achieved this object.

The Chief Inspector was the first to recover. He said in his most authoritative manner,

‘You say that you saw Marsham come to that glass door and open it?’

‘Don’t any of you understand plain English? Of course I saw him-that’s what I came here to tell you! Because I thought he could clear me-and, believe it or not, it wasn’t until I had the words on my tongue that I saw it could mean that the fellow had done it himself.’ He pulled a loud bandanna from his pocket, rubbed his face vigorously with it, and thrust it back again. ‘My word, it’s stinking hot in here!’

Lamb rapped on the table.

‘This is a very serious statement, Professor Richardson.’

The Professor exploded again.

‘Serious? Of course it’s serious! I’m a serious person-I’ve no time to waste over trivialities!’

Lamb rapped again.

‘You say you saw Marsham opening this door at-what time would it be?’

‘Might have been five and twenty past eleven-mightn’t have been as much. I don’t go about looking at my watch.’

‘Could it have been later than that?’