Between Silk and Cyanide

by Leo Marks

  He’d expect a lightning synopsis, which wasn’t possible.

  ‘Answer fully.’

  Was the bloody man telepathic?

  In any event, he should have addressed his question to Nick. He was the expert on Morse technicalities. But Nick’s eyes were still averted.

  Tap tap …

  And his face a forbidden war zone.

  Tap tap … It was the general’s fingers drumming on the desk.

  I decided to answer him in kind.

  Resting my elbow on one end of the Dutch report and my fingertips on the other, I demonstrated to the glowering general that WT operators fell into two main categories: those who waggled their wrists and those who waggled their elbows. The elbow-wagglers were more consistent but if any operator were exceptionally tense or had an attack of ‘Morse cramp’, the slightest deviation in his touch could butcher the indicator groups. The letter N (-.) could be transmitted as A (.-), the letter L (.-..) as Y (-.--), and the commonest letter of all, E (.), could easily become the next commonest letter, T (-).

  Tap tap from the general’s fingers. Too much detail?

  Speeding up my crawling commentary, I explained that monitoring a WT operator’s traffic was like listening to a foreigner with a broken accent, and signalmasters could always distinguish between mistransmitted groups and Morse-mutilated ones for a very simple reason: poor atmospheric conditions affected all the code groups, often making the clear-text impossible to read, whereas an operator’s mistakes affected only individual letters.

  The warning gleam was back. ‘That’s all very well as far as it goes – but what if an indicator group had been wrongly encoded, then wrongly transmitted, and atmospheric conditions were bad? How could you detect the original mistake?’

  How indeed?

  ‘It would be quite beyond us, sir – and it’s about as likely as C giving SOE a vote of confidence …’

  The atmosphere deteriorated sharply but for once my courage didn’t.

  ‘… and, sir … if the point of your questions is to suggest that we have had indecipherables from Holland due to coding mistakes but wrongly attributed them to other causes, could you please explain why no Dutch agent has ever misnumbered a transposition key, “hatted” a column, misspelt a word in his poem or made any of the other coding mistakes which free agents will continue to make until WOKs are introduced?’

  ‘Sit down, Marks,’ he said quietly.

  I didn’t realise I wasn’t and complied forthwith.

  He looked at me like a marksman reassessing his target. Then a new thought marched into his eyes, and he began rummaging through the ‘Giskes evidence’ which was stacked in front of him. ‘Where’s that damned indecipherable? I want another look at how it looked to Boni.’

  Two ‘looks’ in one sentence? – had something disturbed him?

  He spent several minutes (the equivalent of hours by normal standards) studying the jumble of malformed words which Boni had received.

  ‘Marks. Are you telling me you don’t know of a single agent who might be able to decode this message?’

  ‘Knut Haugland, sir – if he had the time.’

  ‘Did you brief him?’

  ‘Yes, sir.’

  ‘Did you brief Boni?’

  ‘No, sir.’

  ‘Then how do you know he’s not another Knut Haugland?’

  Opening my briefcase, I handed him Boni’s training-school reports. These showed that he was a first-class WT operator but only an average coder who was frequently careless and took short cuts which seldom worked. The instructor strongly recommended more coding practice for Boni before he left for the field.

  The general immediately asked if I’d read Knut Haugland’s report.

  ‘Yes, sir.’

  ‘How did his instructor assess him?’

  ‘Below average, sir.’

  ‘Then why do you trust the judgement of Boni’s instructor if you can’t trust Haugland’s?’

  ‘It might save time, sir, if I showed you the only thing I have any faith in at all …’ Delving once more into my briefcase, I handed him a complete list of the keys the girls had tried in their blanket attack on Boni’s indecipherable. There were six thousand of them.

  He seemed astonished when I explained what they were. ‘Do you always go to these lengths to break an indecipherable?’ It was the first time his tone had been muted.

  ‘That’s only phase one, sir. Some indecipherables take days to break. The girls never give up.’

  ‘And WOKs would put a stop to these indecipherables?’

  ‘And to a lot of other things, sir. Including meaningless security checks.’

  The gleam again. ‘Did you tell the coders this was a deliberate indecipherable?’

  ‘No, sir! They all think it was caused by a teleprinting mistake.’

  He brusquely conceded that Boni had little or no chance of breaking the indecipherable, but before I could say ‘Hallelujah’ – or Marks & Co.’s equivalent, ‘He’s paid in cash’ – he’d begun demolishing the whole concept of Plan Giskes.

  Why should Boni risk coming on the air to ask for the indecipherable to be repeated when he had all the operational instructions he needed from his other messages? And why was I so convinced that he’d do so ‘by reflex’? In his experience agents were unpredictable at the best of times, let alone in the middle of dropping operations (as my stomach now was).

  He then targeted my ‘Potato theory’. Just because Boni had informed London of Potato’s indecipherables, it didn’t follow that he’d notify us the moment he received one himself. ‘And if my memory serves me right, it took him the best part of a week to report Potato’s indecipherables. He’s only had yours for three days.’

  Nor could he accept that Boni’s missed skeds were evidence of Giskes’s timing as my anxieties about Holland were based on premises which could easily be wrong! – Incidentally, how did I know so much about Giskes?

  I had to admit that the little I did know had come from Nick.

  He shot his next question at me as quietly as a machine gun can. Did I have similar anxieties about any other country section’s agents?

  Wary now of saying anything, I brusquely informed him that all messages in the poem-code were suspect, and I had no doubt at all that the Germans were running some French and Belgian agents just as skilfully as they were the Dutch. The only difference was that we now had proof that Boni was caught.

  He reminded me sharply that he was still far from convinced that my ingenious little trick had proved anything at all except that I was capable of heinous misconduct. He then proceeded to make three things clear:

  1 There was a place in SOE for the unorthodox but not for the wholly undisciplined.

  2 My unauthorised actions were absolutely inexcusable.

  3 If the country sections found out that their traffic had been tampered with they’d lose all confidence in the Signals directorate, and ideas like WOKs wouldn’t even get a hearing.

  He added that he’d dismiss me on the spot if Nick hadn’t urged him to give me one more chance. As it was, he was still in two minds as to what should be done about me.

  Death by drowning, by exploding minefields, by—

  ‘But before discussing your future, if any, in SOE I must make one thing absolutely clear to you.’

  He then made a statement which caused a drop of perspiration to parachute from the end of my nose and land on the edge of his desk.

  He was satisfied that my report raised enough questions to warrant an independent investigation into the Dutch agents’ security and he would institute one immediately. He was particularly disturbed about the interlocking of so many WT circuits, which was potentially extremely dangerous. He got a quick nod from my saviour.

  Before I could begin to absorb the miracle he produced his caveats.

  If I wished to stay in SOE, under no circumstances must I discuss Holland with anyone but Nick and himself. And if I had any further anxieties about the Dutch
I must consult Nick immediately. ‘And if for any reason he’s not available, you will telephone Miss Jackson and come direct to me. Is that understood?’

  ‘Yes, sir.’

  He looked harder at me than at any time since the meeting began. ‘If you’ve been up to anything else without Colonel Nicholls’s permission you’d better stop it at once. I don’t want to curb your initiative but this sort of thing must never happen again. Is that understood?’

  ‘Yes, sir.’

  I must have used the wrong tone because I got his blackest look yet. ‘You’re not the only one who’s concerned about our agents’ safety. Certain steps are taken that you know nothing about, and you will no longer question the decisions we make or ask questions about them. Is that also understood?’

  ‘Yes, sir.’

  Once again Celt met Jew on their favourite frontier, and I could tell from his expression that my passport was in order. He signalled my dismissal and I stood up to go.

  ‘For your information, there’s one more thing. I am not one of those pricks who found the report too technical. As far as I’m concerned, it wasn’t technical enough.’

  Is that a twinkle that I see before me, the handle towards my throat?

  I didn’t discuss the meeting with Heffer when I reeled into his office next morning, nor did he expect me to. But I did tell him that Nick had intervened to help me keep my job.

  ‘You sound surprised,’ he said. ‘What else would you expect? But I think you should know what really saved your bacon – no insult intended to the pig.’ He kept me waiting for a puff. ‘It was Tiltman.’

  I was beyond surprise by this time.

  ‘Can you guess what he said about you to CD and Gubbins?’

  ‘That I serve the best black-market lunch in London?’

  ‘Something a bit more unexpected. He said that as far as Bletchley was concerned you were the one that got away!’

  He added an afterthought: ‘It wouldn’t suit SOE if you got away to Bletchley.’

  But I still couldn’t get away from my failure to devise a letter one-time pad …

  TWENTY-SEVEN

  Criminal Negligence

  I had a feeling I couldn’t define that there was something in Boni’s traffic which I’d completely overlooked and that some action was called for that I’d neglected to take.

  More convinced than ever that every message he sent was some Dutch agent’s obituary notice, I decided to become Boni-immersed, and divided his traffic into two categories:

  1 His normal traffic, if the term could be applied to it

  2 His ‘special messages’ from Victory and Vinus, which he’d begun transmitting last December.

  His Normal Traffic

  The March moon period (which began on the 11th) was a bumper one for him. He was alerted on the 10th that seven containers would be dropped any time from tomorrow night onwards and that the 10,000 florins he’d been waiting for since January would be inside a cell marked with a white cross. He must tell London at once if Parsnip and the reception committee could handle the containers in two separate deliveries.

  Boni confirmed on the 13th that separate containers would present no problems and asked for two sets of bicycle tyres to be included for the reception committee.

  Could anything be more persuasive than this last-moment request for bicycle tyres? Giskes deserved the 10,000 florins for his attention to detail.

  But respect for him brought me no closer to my elusive mistake, and I reluctantly turned to the traffic, where I was likeliest to find it.

  Every time I read the messages which Boni transmitted on behalf of Victory and Vinus my waxy inner ear started to throb. Desperate to dredge up whatever was worrying me, I made a precis in longhand of the Victory–Vinus–Boni relationship in the hope that the tedium of trying to decipher my own handwriting would force me to acknowledge what I’d overlooked.

  The Victory–Vinus–Boni Relationship

  Victory (real name Koos Vorrinck) was a senior member of the National Committee and one of Holland’s leading politicians. A dedicated partisan, he worked independently of SOE but badly needed to communicate with the Dutch government-in-exile, and asked his friend Vinus (real name Levinus van Looe) to provide him with a WT operator.

  Vinus, a member of the Cabbage–Parsnip group, asked London if Boni could handle Victory’s traffic until new operators could be sent in, and with N section’s consent he began transmitting it last December and had continued ever since.

  All the messages were long, and most of them contained information which London already knew, but N section regularly replied to them and sent copies (some of them accurate) to the government-in-exile, who also replied to them. Via Boni.

  One of these messages (number 60 of 16 February) had puzzled me when I first read it and caused me to ask questions which had nothing to do with my role as a cryptographer.

  It reported that a Gestapo agent named Johnny was telling Dutch citizens that he’d returned from London with important instructions for them from the Dutch government, and Victory wanted the BBC to start broadcasting messages twice daily warning the Dutch public to have no dealings with him. The broadcasts should begin at once, ‘before Johnny did more damage’.

  London replied on 17 February asking for a detailed description of Johnny, as without one the warnings would have little effect! The broadcasts would begin as soon as they received it.

  Johnny’s vital statistics didn’t arrive for another three weeks. On 12 March Boni transmitted a detailed description of the alleged agent (he sounded remarkably like Father’s partner Mark Cohen, whose movements I’d check) but the message made no attempt to explain the delay.

  Surely experienced agents like Vinus didn’t need to be told that a detailed description was vital? And surely someone of Victory’s calibre would have provided it in the first place? So why had it taken three weeks to arrive?

  Because Johnny didn’t exist?

  In which case, I envied him.

  The feeling that I’d not only been careless with the Dutch traffic but criminally negligent was now a conviction. My last chance of pinpointing it lay in a segment of Boni’s traffic which had raised his transmissions to a different level.

  On 28 December he reported that Vinus had asked him to transmit an important communication from Victory to Queen Wilhelmina. The communication would consist of twelve separate messages which would add up to one long telegram. He asked London’s permission to proceed.

  On 1 January he was authorised to send the twelve messages on two conditions:

  1 That they didn’t endanger his other transmissions

  2 That they weren’t of a purely political nature.

  On 14 January Boni agreed to send the messages if their importance warranted it, but admitted for the first time that Victory’s traffic had begun to interfere with his other transmissions (another mastertouch?). He left the final decision about future Victory messages to London.

  On 15 January (number 54) he was authorised to start transmitting the queen’s messages, and told to await instructions regarding further Victory messages.

  On 17 January he transmitted the first of the twelve messages and the last of them was received on 30 January.

  Far from being purely political (a contradiction in terms?), Victory’s messages were highly militant. They cited many examples of German brutality and urged immediate reprisals. German cities should be bombed, leading Nazis in Holland targeted and Dutch citizens told that they would have the full support of the queen if they engaged in acts of sabotage and resistance against their German oppressors.

  It took the government-in-exile the best part of a month to reply to Victory, which was either an insult to his judgement or a tribute to his eloquence.

  Finally, on 2 March, they sent him a message via Boni (number 64) thanking him on the queen’s behalf for his twelve messages. But their reply made clear that although they were aware of the Germans’ brutality, they feared that the meas
ures which he advocated would result in even greater oppression and urged him to use his considerable influence to discourage any form of retaliation at the present time.

  Victory made no direct response to this. But on 5 March Boni informed London that he’d received a further batch of ‘Victory messages’ from Vinus and that in the absence of instructions to the contrary he would begin transmitting them, which he proceeded to do with his customary skill on 5 and 11 March. One message in particular redefined ‘Dutch courage’. It stated that in readiness for the German collapse, the National Committee was attempting to form a caretaker government which would remain in office until Queen Wilhelmina and the Dutch government returned to Holland. All six members of the National Committee including Vorrinck were referred to by name in this message, which had been transmitted in a poem-code.

  A cryptographer-in-exile realised that if he spent any more time searching for a mistake which might be illusory instead of producing new codes, Giskes’s victory would be even more complete. I put the Dutch traffic aside and resumed my attempts to devise a letter one-time pad. Three hours later I realised what I’d overlooked. A doctor would have been struck off for it, a soldier court-martialled, an accountant promoted. I’d been so busy trying to prove that Boni was captured that I’d given no thought whatever to prolonging his life.

  I remembered Buckmaster’s dictum: ‘The best way to help a captured agent is to pretend that he’s free.’ I’d taken no such steps to help Boni. Instead I’d sent him a deliberate indecipherable.

  Giskes may not have realised it was a trap, as he had no reason to credit Baker Street’s poem-bound amateurs with the ability to set one. But surely he’d expect even SOE’s code department to issue some elementary precautions when a WT operator transmitted messages to a head of state, and received her replies, and disclosed the existence of the National Committee, and named its members? Yet all I’d done was ask N section to warn Vinus to use different prefixes for his and Victory’s messages (number 48 of 28 December) and issued new poems for the Cabbage group.