CISRA Puzzle Competition 2011 - Solutions

5C. Caesar Salad

Each line seems to be cluing two different words. Some clues have several plausible answers, but even so some useful properties can be observed from some of the more likely candidates. We might guess, for instance, at: panda, dank, hero, bunny, sleep, viva, torus, fadge, vane, jobs, thumbs, anno, reef, jerky, hawk, dodo, dolls, wheel, leap, Piet.

Looking at the pairs available there, we might observe that both answers in a pair have (or can be made to have) the same number of letters. Adjusting further answers to attempt to meet this property can narrow answers further. After doing so, a stronger pattern may be noticed: Each pair has the same "letter pattern". Admittedly this is rarely a strong condition, but the pairs bunny/sleep, anno/reef, and dolls/wheel serve to make this plausible.

Further progress comes from realising (quite possibly prompted by the title itself, which may lead some solvers to grasp the puzzle motif immediately) that not just are the letter patterns the same, but each letter in the first word has shifted the same distance in the alphabet (cyclically) to produce the second word. This is a very old ciphering technique called the Caesar cipher. In it, each letter is replaced by the letter a certain number (the shift) of letters later in the alphabet, wrapping around to the start if need be. Julius Caesar is said to have used this cipher with a shift of 3. For instance, IBM is the result of applying the cipher to HAL using a shift of 1 (although this is a coincidence).

This strong property makes it much easier to complete the list of answers, and we get:

Clues	first	second	shift
A group of eight slowly trickles	octad	drips	15
Ailuropoda guitar	panda	dobro	14
Diced fruit	cubed	melon	10
Dark, dank protagonist	dank	hero	4
Rabit slumber	bunny	sleep	17
Long live grandmothers!	viva	nans	18
Doughnut-shape Irish potato bread	torus	fadge	12
Wind measuring-instrument occupations	vane	jobs	14
Violet-ish with more dye	purply	inkier	19
Masculine opposable digits	manful	thumbs	7
Nut big cat	pecan	tiger	4
In the year of an underwater rock ledge	anno	reef	17
Horses pouffe	steeds	tuffet	1
Scythe-shaft dried meat	snath	jerky	17
Accipitrinae pastries	hawk	pies	8
Extinct bird father	dodo	papa	12
Double unsliced bread	twin	loaf	18
Mannequins round transport device	dolls	wheel	19
Flowerpot runs slowly	vase	jogs	14
No place renouncer	nowhere	abjurer	13
Jump Mondriaan	leap	Piet	4

The natural step to take at this point is to turn those shift values into letters. Doing so in the usual fashion gives ONJDQR LNSGDQ AQHLRSMND, which is not enlightening. However, when converting Caesar cipher shifts to letters, the convention is to use A to indicate no shift, B for a shift of 1, and so forth (see, for example, the Vigenère square here). In practice, this means we must shift one letter further in the alphabet in our conversion. (One could also simply try shifting the letter sequence by various amounts until a message emerges.) Doing so produces the message: POKERS MOTHER BRIMSTONE.

This is another clue of the same form encountered already. "Poker's mother" refers to the venerable card game primero, and brimstone is another name for the chemical element sulphur. These two words are shifts of one another (with a shift of 3), confirming the correctness. The answer is PRIMERO SULPHUR.