‘Did what, sir?’
Jowett put another match to his pipe. ‘Well, you were given the job of constructing two identical infernal machines, one of which was to be used to demonstrate your skill as a dynamitard, while the other was afterwards put into the submarine boat. If I’ve understood your account of it correctly, you had no control over the selection of the bombs for these purposes, and the setting of the clocks was most stringently supervised.’
‘Quite correct, sir.’
‘So you couldn’t have interfered with the machines after you had made them.’
‘That’s right, sir.’
‘Yet the gazebo was blown to bits, while the bomb in the submarine boat failed to detonate. That’s either extraordinary good luck or so ingenious that the explanation eludes me. I repeat, how did you do it?’
Cribb hesitated, tugging his side-whiskers, knowing, as conjurers do, that explanations add nothing to spectacular effects. He really could not refuse to answer Jowett’s question, however. ‘Well, sir. It was very simple. When I built the machines I made sure that neither of ’em would work. I carefully removed all the powder from the cartridges the pistols fired. So they couldn’t go off, you see?’
‘Frankly, I don’t,’ said Jowett. ‘One of them destroyed the gazebo, so it must have gone off.’
‘I’m afraid not, sir,’ said Cribb apologetically. ‘That box is probably still lying intact at the bottom of the lake. It was a straightforward charge of dynamite that blew up the gazebo. I removed a couple of bricks from the underside of one of the arches above the water and stuffed in several discs of Atlas Powder. Then I attached a piece of slow-match- that’s a slow-burning fuse, sir-and gave it an hour. It was slightly late in working, but near enough to be convincing. That’s a far more reliable way of blowing up a gazebo than using clocks and detonators nine feet under the water.’
‘So that was it,’ said Jowett, with disappointment in his voice. ‘I thought it must be something cleverer than that.’
Cribb stoically accepted the rebuke. He watched Jowett make another attempt to light his pipe, before saying, ‘I was rather wondering if you had any idea what would happen to Miss McGee and her father, sir.’
Jowett shook his head. ‘Not much at all, Sergeant. From what you have told me, the major criminals perished in the explosion. Between you and me, there are reasons why it might be necessary to keep this case out of the courts altogether. The-er-party on the Hildegarde were blissfully unaware that the submarine boat was full of dynamite, and it is probably best all round if they remain unenlightened on that point. There is not much to be gained from bringing a helpless cripple like McGee before a judge, and his daughter seems to have played quite an insignificant part in the proceedings, from what you say. We’ll keep an eye on her through the Special Branch, of course. Got to give those fellows something to occupy them, eh?’
‘I suppose so, sir,’ conceded Cribb, a little wistfully.
‘I’ve got some capital news for you, though,’ Jowett went on. ‘Your work in this affair has not gone unrecognised, Cribb.’
‘Really, sir?’
‘Depend upon it, if a man in my charge does something as creditable as you have done, it gets reported to higher quarters.’
‘Thank you, sir.’
‘Yes, the Commissioner himself has heard about your exploits, and I believe he is more than a little impressed. He has gone so far as to make a personal recommendation, Cribb.’
Cribb came smartly to attention.
‘He has recommended-and, of course, it has been agreed by myself-that you be relieved from normal duties for the next three weeks to complete the explosives course at Woolwich Arsenal, which you had to leave prematurely. Congratulations! You will know more about explosives than anyone at Scotland Yard, Sergeant. You start tomorrow morning, at the point where you left off. Craters, I believe, and the effects of-’
‘Blast,’ said Cribb, with feeling.