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In general, there is no alternative but experiment (directed by probabilities) of every tongue known to him who attempts the solution, until the true one be attained. But, with the cipher now before us, all difficulty was removed by the signature. The pun upon the word 'Kidd' is appreciable in no other language than the English. But for this consideration I should have begun my attempts with the Spanish and French, as the tongues in which a secret of this kind would most naturally have been written by a pirate of the Spanish main. As it was, I assumed the cryptograph to be English.

"You observe there are no divisions between the words. Had there been divisions, the task would have been comparatively easy. In such case I should have commenced with a collation and analysis of the shorter words, and had a word of a single letter occurred, as is most likely, a or /, for example,) I should have considered the solution as assured. But, there being no division, my first step was to ascertain the predominant letters, as well as the least frequent. Counting all, I constructed a table, thus:

"Of the character 8 there are 33.
; „ 26.

[table]

"Now, in English, the letter which most frequently occurs is e. Afterwards, the succession runs thus: aoidhnrstuy cfg Imwbkpqxz. E predominates so remarkably that an individual sentence of any length is rarely seen, in which it is not the prevailing character.

Here, then, we have, in the very beginning, the groundwork for something more than a mere guess. The general use which may be made of the table is obvious; but in this particular cipher we shall onlyvery partially require its aid. As our predominant character is 8, we will commence by assuming it as the e of the natural alphabet. To verify the supposition, let us observe if the 8 be seen often in couples—for e is doubled with great frequency in English—in such words, for example, as 'meet,' 'fleet,' 'speed, 'seen,' 'been,' 'agree,' &c. In the present instance, we see it doubled no less than five times, although the cryptograph is brief.

"Let us assume 8, then, as e. Now, of all words in the language, 'the' is most usual; let us see, therefore, whether there are not repetitions of any three characters, in the same order of collocation, the last of them being 8. If we discover repetitions of such letters, so arranged, they will most probably represent the word 'the.' Upon inspection, we find no less than seven such arrangements, the characters being ;48. We may, therefore, assume that ; represents t, 4 represents h, and 8 represents e—the last being now well confirmed. Thus a great step has been taken.

"But, having established a single word, we are enabled to establish a vastly important point; that is to say, several commencements and terminations of other words. Let us refer, for example, to the last instance but one, in which the combinations ;48 occurs—not far from the end of the cipher. We knew that the ; immediately ensuing is the commencement of a word, and of the six characters succeeding this 'the,' we are cognizant of no less than five. Let us set these characters down, thus, by the letters we know them to represent, leaving a space for the unknown

t eeth. "Here we are enabled at once to discard the 'th,' as forming no portion of the word commencing with the first t; since, by experiment of the entire alphabet for a letter adapted to the vacancy, we perceive that no word can be formed of which this th can be a part. We are thus narrowed into

t ee, and, going through the alphabet, if necessary, as before, we arrive at the word 'tree,' as the sole possible reading. We thus gain another letter, r, represented by (, with the words 'the tree,' in juxtaposition.

"Looking beyond these words, for a short distance, we again see the combination ;48, and employ it by way of termination to what immediately precedes. We have thus this arrangement:

the tree ;4( j?34 the, or, substituting the natural letters, where known, it reads thus:

the tree thrj?3h the. '■ Now, if in place of the unknown characters, we leave blank spaces, or substitute dots, we read thus:

the tree thr. . .h the, when the word 'through' makes itself evident at once. But this discovery gives us three new letters, o, u and g, represented by % ? and 8.

"Looking now, narrowly, through the cipher for combinations of known characters, we find, not very far from the beginning, this arrangement:

83(88, or cgree, which, plainly, is the conclusion of the word ' degree,' and gives us another letter, d, represented by f.

"Four letters beyond the word ' degree,' we perceive the combination

;46(;88. "Translating the known characters, and representing the unknown by a dot, as before, we read thus: thr .tee,

an arrangement immediately suggestively of the word 'thirteen,' and again furnishing us with two new characters, i and n, represented hy 6 and *.

"Referring now to the beginning of the cryptograph, we find the combination,

53#t.

"Translating, as before, we obtain — 'good, which assures us that the first letter is A, and that the first two words are ' A good.'

"It is now time that we arrange our key, as far as discovered, in a tabular form, to avoid confusion. It will stand thus:

5 represents a
t » d
e

g
h

t

"We have, therefore, no less than ten of the most important letters represented, and it will be unnecessary to proceed with the details of the solution. I have said enough to convince you that ciphers of this nature are readily soluble, and to give you some insight into the rationale of their development. But be assured that the specimen before us appertains to the very simplest species of cryptograph. It now only remains to give you the full translation of the characters upon the parchment, as unriddled. Here it is:

"' A good glass in the bishop's hostel in the devil7s seat forty-one degrees and thirteen minutes northeast and by northmain branch seventh limb east side shoot from the left eye of the death's-head a bee line from the tree through the shot fifty feet out.'"

« But," said I," the enigma seems still in as bad a condition as ever. How is it possible to extort a meaning from all this jargon about 'devil's seats,' 'death's-heads," and * bishop's hotels ?''

"I confess," replied Legrand, "that the matter still wears a serious aspect, when regarded with a casual glance. My first endeavour was to divide the sentence into the natural division intended by th e cryptographist.''

"You mean, to punctuate it?"

"Somethingof thatkind."

"But how was it possible to effect this?"

[graphic]
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