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Present Day by Horvendile

Posted by shirleycurran on 15 January 2016

Our initial reaction on downloading Horvendile’s ‘Present Day’ was a delighted ‘Well, that’s a big grid, it will keep us busy for the rest of Christmas Day – Present Day – that’s today. It must be about Christmas boxes. What fun!’ Then realization dawned. That odious word ‘Playfair’ appeared, and not just that. ‘Every entry is Playfair-encoded using the code-square that must be completed in the centre of the grid.’ Oh well, I imagine the ‘four unclued entries’ will give us a hint about the keyword. But no, it gets worse, as they are considered ‘entries’ so clearly are to be encoded too. How on earth are we to find the keyword?

Of course, I scan the clues to check that Horvendile qualifies as an applicant for the Listener Merry Tipplers gang, but consternation! Perhaps we can award provisional entry on the basis of ‘Cause of special pain once (4)’ giving SAKE, but he seems to be determined to give the alcohol a miss in his clues, with ‘Welcome in NZ, I’m here working with AA (HAEREMAI). (Note to self, find him and make sure he has a drink in his hand at the coming Listener Setters’ Dinner!)

Complete plain text grid. What now!

Complete plain text grid.
What now!

Nothing to be done! Call this a crossword? We can’t cross any words and simply have to cold solve – and we cold solve and cold solve and … until almost midnight when we have solutions to forty-five of the fifty-six clues. Now come on, Numpty, you are being rather tough on poor Horvendile; some of these were super clues and what sort of mind can calculate how the enciphered clues are going to intersect to create a working grid. I just can’t imagine how he/she (well, there are two or three women amongst the setters) managed this feat and hope she/he will give us a setter’s blog.

For example, we smiled at ‘Work with great singer, one barely seen up (6)’ (GO + DIVA – well, she was naked up on a horse wasn’t she?) ‘Wanton cop abroad touring Romania (6)’ (That’s our French FLIC round RO, having a FROLIC) and ‘Cheese is dear around mid-January in Paris (6)’ (more local fare for us CHERE round (jan)V(ier) giving CHEVRE).

Of course we ‘cheat’ if using Braingle or Quinapalus is cheating and I truly admire anyone who solved this crossword without an Internet tool. Poor Mr Green, who not only has to mark the grids that come to him with just two normal words at the start of those Playfair squares, but also solves and functions without the help of the Internet.

I stay up well after midnight fiddling with potential ways into this crossword. We have already produced some data, several letters that have to be related. For example, I and P must appear in the same row (first); E and H must appear in the same row (could be the second but probably the third); O and R must be in the same column – and so on. But are we going to have to make these calculations for the entire Playfair square in order to find that key word? WAMPUS is a help since that W cannot encipher to itself, and we make the guess that the WY of WYCH will become the YZ of our Playfair square so that, putatively, we will have (U)VWYZ at the end of our square and X in our keyword.

I refuse to admit to how much time I wasted on XMASTIDE and other X words. We had WHIP at 23ac but no Internet tool, when I brainlessly fed in my IP enciphering to XM, and WY to YZ would give me any X words in the suggested keywords (or any suggestions at all). However, the list provided by that last couple included PACKING BOX and when I paired IP with PA, that seemed to work and seemed appropriate – and, of course, P in that cell, led to I at the end of the row. Of course, after we had used that keyword for a while, it failed, as sections of intersecting words didn’t agree. Back to the head-scratching. But ‘PACKING BOXES’ was provided and Eureka, that worked!

Later, a friend who made far less of a lucky leap (Internet aided) than I did, explained his logic – how, using those calculations of the placing of pairs of letters, he constructed the basis of his square. I include it here.

 “I worked with the general principle that if a pair of letters encode into a pair sharing a row (column) then the plaintext pair must also be in that row (column).  E.g. if you know AB->XY and X & Y are in the same row then A & B are also in that row. As for coming up with the key phrase, if (a big if) you can cold-solve those clues, I think you can infer:

WHIP: First row is PxxxI

BORATE: 2nd row is xxBOx

SHTETL: 4th row is LxxxT

WYCH: 5th row is xxWYx (which must be xxWYZ so X is in the key)

GODIVA: 2nd col in AxxxV

FROLIC: 4th col is xxFRx)

 So this much is deducible

PA..I
..BO.

…F.

L…T

UVWYZ   the U is forced of course”

 Enciphered 001Next morning, we laboriously completed our enciphered grid, which, of course, allowed us to decipher the letters of the clues that were still unsolved (KENSINGTON, S’BLOOD, VULNED, FINSKO, DAFTAR; seriously! How will my friends react when I produce those in conversation this week?) and we were left with four glaring spaces where we had to put thematic words. ??ST, ??NI???? SH??, and ????ND?? Four ‘PACKING BOXES’?

Oh how grateful I am for TEA. I simply fed those, individually into TEA and chose the most likely words from the many offered and enciphered them. No CONIFERS didn’t work (no Christmas cheer), but CANISTER did encode to KCXPHMFL, which fitted the encoded pairs and single letters already in place. In the same way, we found (with Mrs Bradford’s help) SOLANDER encoding to FGMPBEFL, and KIST and SHOE. I grumbled at first that SHOE was an adjective and the others were nounal, but no, Chambers tells me a SHOE is a sort of box for cards.

My clever friend was far more technical and I append his method.

“You can use TEA to give you possibilities for each theme word since if the cyphertext letter is x the plaintext must be one of the 9 (or 10 since I=J) letters in the same row or column as x. So the four patterns are:

.[pakibdqw]ni[esdfixtz].[esdhkory].

.[nboxasmv].[ackinelu]nd[esdhkory].

[packxhtz].st

sh.[esdhkory]”

 This was tough, tough, tough. Had we not managed to complete all this year’s Listener crosswords (whether correctly or not I do not know; it is too distressing to check and find an error as early as January so once they are in the mailbox, we forget them) I think we would have abandoned at the start. And to think that I complained about Sabre’s Knights’ moves, you can come back, Sabre, all is forgiven!

But seriously, congratulations Horvendile. If this really is a début and you are not Mash, Quinapalus or Sabre in disguise (and I did decipher Horvendile but it gave only fx ly je hc js) then it was a most impressive one.

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2 Responses to “Present Day by Horvendile”

  1. apaultaylor said

    We had twigged that the clues that encroached two cells into the code square forced the placement of some of its letters, but were held up for longer than I’d care to admit by the fact that my working copy of the code square had six rows…

    For checking proposes I made a little program to do the Playfair en-/de-ciphering for me, I’ve tidied it up a bit in case it’s useful to anyone else for any equally ridiculous puzzles that might appear in the future:

    https://dl.dropboxusercontent.com/u/27431375/playfair/playfair.html

  2. Jaguar said

    Although this was a seriously tough slog, in the long run it taught me so much about the playfair cipher and working with it. For a start, your technical friend is not quite correct, and you can do even better if you know the code word and either of the two letters to be encoded in a word. For example, using PACKINGBOXES I’ve encoded the string abacadae… and you can organise the results as follows:

    plaintext:
    ab ad aq aw ap ac ai ak
    an ae al au
    ao af ar ay
    as am av ag
    ax ah at az

    Ciphertext

    cg cs cm cv ca ck cp ci
    pg ps pm pv
    kg ks km kv
    gs gm gv ga
    ig is im iv

    The decryption table is almost the same:

    Ciphertext:

    ab ad aq aw
    an ae al au ac ap ai ak
    ao af ar ay
    as am av ag
    ax ah at az

    Plaintext

    cg cs cm cv
    pg ps pm pv pa pi pk pc
    kg ks km kv
    vg vs vm va
    ig is im iv

    You can do a similar thing with fixing the second letter and produced more patterns — the take-home message is that Playfair ciphers are fiddly but the constraints are quite powerful. Using this on eg DE?F you could constrain the last letter to be one of just ESDHO and then the last pair options can be neatly tabulated, eg a last-letter O pairs only with KRFY, or E/H/S with KORY, while if F decodes to D only then is the first letter fairly unconstrained (one of KORYSHFE). All the same, one can try a much-reduced space of options for DE?F, trying patterns like sh[fkry]o or sh[kory][she] or sh[efhkorsy]d, finally giving only SHED, SHOE or SHOD as the word options (compared with “shad shah shay shed shes shmo shod shoe shoo” that fit the pattern sh.[esdhkory] according to quinapalus/ UKACD).

    Essentially the rule is then that a letter can only encode/ decode to five other letters, which are the four in its row and the one immediately below/ above it, and when paired with the remaining alphabet the second letter can only be encoded/ decoded to eight letters, which are the letters in the same row/ column as the known letter of the pair, with an overwhelming preference for letters in the same column.

    The patterns are quite handy to know and use for future playfairs! (really this means that outside crosswords, it’s quite a useless code — the patterns are too constraining. Never mind).

    Oh and, thanks, Horvendile.

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