Solving Cryptograms
By Ajax
When working on an easy crypt, look for common words such as
the, and,
in, and of. Try to
identify words with repeated letters, such as ABCADB (probably
people, though it could be proper or a few other, less common words as well), or
EFGGEH (almost certainly little), or a
long word ending in -IJKK (-ness). Some solvers keep lists of the
common "pattern words" they encounter; books of pattern and
nonpattern word lists are also available for the dedicated
solver.
Letter frequency is a useful clue in easy crypts but less so
in harder ones, where the message has probably been deliberately
designed to avoid the usual frequencies. The most frequent
letters in English are E, T, A, O, I, N, S, H, R, D, L, and U in
that order (some studies have given slightly different results).
These frequencies are only tendencies, not laws of nature; even
in easy crypts, don't expect to find this exact frequency. For
harder crypts, the best approach is often to determine which
letters stand for consonants and which stand for vowels.
Experienced crypt-solvers feel that once they have that
information, the rest is relatively easy. Many systems for
identifying consonants and vowels have been developed over the
years, some of them involving considerable calculation. The
method given here is not the most powerful, but it's relatively
easy to use and a good one for beginners.
Spotting Vowels and Consonants
- Make a record of how many times each letter in the crypt is
used, how many times the letter starts words, and how many
times it ends words.
- Assume that any letter used only once or twice in the crypt
is a consonant. Put an identifying mark around letters used
once and another mark around letters used twice.
- If the number of times a letter occurs at the start and end
of words is half or more than half the total number of times
the letter occurs, assume it is a consonant. Underline such
letters.
- If a letter occurs between consonants identified in steps 2
and 3, assume it's a vowel. Put an X under assumed vowels.
- Two letters that reverse with each other (for example, when
the combinations -JY- and -YJ- both appear in the crypt) are
usually one vowel and one consonant. Other factors such as
relative frequency can often indicate which is which.
- Marking vowels and consonants as suggested leads to the
spotting of other vowels and consonants. For example, if a
letter occurs next to vowels and starts or ends some words,
it's likely to be a consonant. Judge based on all the
occurrences of a letter, not just one or two. Keep trying
combinations of vowels and consonants until one arrangement
seems to fit throughout.
Identifying Letters
Now try to identify some letters in the cryptogram, and from
these, go on to whole words. This usually takes trial and error,
but here are some tips:
- When two consonants start a word, the second is often H, L,
or R. You can distinguish H from the other two because it very
rarely appears after a vowel and very often before one; L and R
appear freely both before and after vowels.
- A consonant that often follows a vowel but seldom precedes
one is often N.
- A vowel frequently found in third-to-last position is often
I, as in -ing, -ion, -ive, and other endings.
- Consonants that end several words may be D, S, or T.
- Three consonants together at the end of a word may be -ght
or -tch. Four consonants may be -ghts.
- Look for words that may represent the prepositions
above, after,
amid(st), among(st), behind,
beyond, from,
over, upon,
into, or with.
It's very difficult to construct a message that avoids all
prepositions.
- Look for prefixes like ex-, over-, un-, or up-.
- Look for suffixes like -ed, -er, -man or -men, or
-ful.
- A low-frequency letter at the end of words may be Y.
- The lowest-frequency letter among the assumed vowels may be
Y, as in sylph, nymph, lymph, hymn, myth, lynx, or pachyderm.
- When you make a guess at one word, try out those letters in
other words of the crypt. Once you have two words right, the
rest of the crypt usually comes easily. Remember, keep
guessing! What one mind can devise, another mind can
decode.