"But," said I, returning him the slip, "I am as much in the dark as ever. Were all the jewels of Golconda awaiting me upon my solution of this enigma, I am quite sure that I should be unable to earn them."

"And yet," said Legrand, "the solution is by no means so difficult as you might be led to imagine from the first hasty inspection of the characters. These characters, as any one might readily guess, form a cipher--that is to say, they convey a meaning; but then from what is known of Kidd, I could not suppose him capable of constructing any of the more abstruse cryptographs, I made up my mind, at once, that this was of a simple species--such, however, as would appear, to the crude intellect of the sailor, absolutely insoluble without the key."

"And you really solved it?"

"Readily; I have solved others of an abstruseness ten thousand times greater. Circ.u.mstances, and a certain bias of mind, have led me to take interest in such riddles, and it may well be doubted whether human ingenuity can construct an enigma of the kind which human ingenuity may not, by proper application, resolve. In fact, having once established connected and legible characters, I scarcely gave a thought to the mere difficulty of developing their import.

"In the present case--indeed, in all cases of secret writing--the first question regards the _language_ of the cipher; for the principles of solution, so far, especially, as the more simple ciphers are concerned, depend upon, and are varied by, the genius of the particular idiom. 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 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 a.s.sumed 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 cases I should have commenced with a collation and a.n.a.lysis of the shorter words, and, had a word of a single letter occurred, as is most likely (_a_ or _I_, for example), I should have considered the solution as a.s.sured. 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 characters 8 there are 33.

; " 26 4 " 19 * " 16 [double dagger]) " 13 5 " 14 6 " 11 [dagger]1 " 8 o " 6 92 " 5 :3 " 4 ? " 3 [pilcrow] " 2 --. " 1

"Now, in English, the letter which most frequently occurs is _e_.

Afterward, the succession runs thus: _a o i d h n r s t u y c f g l m w b k p q x z_. 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 only very partially require its aid. As our predominant character is 8, we will commence by a.s.suming 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,' etc. In the present instance we see it doubled no less than five times, although the cryptograph is brief.

"Let us a.s.sume 8, then, as _e_. Now, of all _words_ in the language, 'the' is most usual; let us see, therefore, whether there are not repet.i.tions of any three characters, in the same order of collocation, the last of them being 8. If we discover repet.i.tions 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, a.s.sume 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 combination ;48 occurs--not far from the end of the cipher. We know that the ; immediately ensuing is the commencement of a word, and, of 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 s.p.a.ce 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([dagger]?34 the,

or, subst.i.tuting the natural letters, where known, it reads thus:

the tree thr[double dagger]?3h the.

"Now, if, in the place of the unknown characters, we leave blank s.p.a.ces, or subst.i.tute 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 [double dagger], ?, and 3.

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

83(88, or egree.

which plainly, is the conclusion of the word 'degree,' and gives us another letter, _d_, represented by [dagger].

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

;46(;88

"Translating the known characters, and representing the unknown by dots, as before, we read thus:

th.rtee,

an arrangement immediately suggestive of the word 'thirteen,' and again furnishing us with two new characters, _i_ and _n_, represented by 6 and *.

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

53[double dagger][double dagger][dagger].

"Translating as before, we obtain

.good,

which a.s.sures 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 [dagger] " d 8 " e 3 " g 4 " h 6 " i * " n [double dagger] " o ( " r : " t ? " u

"We have, therefore, no less than eleven 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 a.s.sured 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 gla.s.s in the bishop's hostel in the devil's seat forty-one degrees and thirteen minutes northeast and by north main 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-head,' and 'bishop's hotels?'"

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

"You mean, to punctuate it?"

"Something of that kind."