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Established 1782. Works in all classes of Literature, English and Foreign, chiefly in Catalogues may be had on receipt of twenty-four stamps. ders of Ships-Saint Wulfran-Seven Sermons on the Sacrament, 1631-Stone Altars in English ChurchesTreveris' "Grete Herball": Names of Plants-The Veto at Papal Elections-Inkstand of Wedgwood Ware, 160. REPLIES: Irish Car and Noddy, 163 Sir William Roger, Knt., 165- Badger, 166- Ombre, 167. - The Bookworm, 168 Shakespeare and Arden, 169-"Parson and Bacon," 171-A'Beckett's Murderers: Somersetshire Traditions, Ib.- Lady Grimston's Grave in Tewin Churchyard Mural Painting in Starston Church, NorfolkPortrait of John Kay-"Though lost to Sight, to Memory dear" - The Pronunciation of Greek and Latin - The Irish Planxty: "Bumper Squire Jones". Rev. Samuel Henley - Dragon - Fishermen in the Olden Time Holty, the German Poet - Hampshire Country Churchyard: Pepys's "Diary Timothy Dexter" Galimatias"-Saarbrück Custom-The Apocalypse - Caliban Who is a Laird? - Old Sandown Castle, Isle of WightSmijth Hints to Chairmen - Queen Elizabeth: Real Persons in "The Faerie Queen - Ballasalley — Signitary and Signataries, &c., 172. Notes on Books, &c. ,, Notes. CRYPTOGRAPHY. A cryptograph, or, as it is not unfrequently termed, a cipher, is a message (written or telegraphed as the case may be) of which the meaning is rendered unintelligible to all unacquainted with the rules followed in its construction. These rules, privately agreed upon by the parties corresponding, usually apply to the substitution of symbols for letters: sometimes also, but less frequently, to a systematic misplacement of the letters from their proper positions in a word. They admit of almost endless variety. The process of finding out the rule by an analytical investigation of the cipher is called deciphering, and the true meaning thus obtained, the evolution. The operation is often a difficult, if not impossible one, and has occasionally engaged the attention of very profound thinkers. Methods of secret communication, somewhat resembling modern cipher, appear to have been practised in very early times. The scytala of the Spartans has been often considered as forming an early link in its development. During the last two or three centuries numerous improved systems have been invented, and frequently employed both in matters of national importance and in the more ordinary affairs of life. In our day cipher lends its aid to politics, war, commerce, love, and even, occasionally, to crime. A mystic line in a column of newspaper advertisements-to the uninitiated a senseless jumble of marks and letters-may often convey the message of a lover to his mistress; or it may sometimes be the friendly caution from a thief to his "pal." During the civil wars at the beginning of the seventeenth century, cipher dispatches were so much in vogue that each army seems to have employed experts for the evolution of any it might capture from the other side. Of those men who made deciphering a study and profession pro tem., perhaps the most remarkable was Wallis, the leading mathematician of his time. It is, indeed, chiefly in war, when communications between generals of division and others must pass through an enemy's country, that cipher assumes its greatest importance, for the messages in many cases can be trusted in no other form. Written in cipher they conceal from the enemy, should he intercept them, information and orders respecting future operations, on the carrying out of which possibly the fate of a campaign depends. Of course this is supposing him unable to evolve their meaning. Having said thus much respecting the uses to which cipher may be applied, I proceed to describe very briefly several systems more or less intricate. In devising rules for the construction of a message, the following conditions ought to be attended to: 1. The cipher produced must be sufficiently intricate as to render its evolution under all probable circumstances hardly possible. Theoretically no ordinary cryptograph of more than a certain length ought, perhaps, to be considered quite proof against unravelment when submitted to a clever expert-allowing him unlimited time; but practically, when time is an object, many are so. 2. The rules must be concise and easily remembered. 3. They ought to be of such a nature that their application both directly to the construction and inversely to the reading of a cipher shall be simple and expeditious processes. It would be absurd were a general on the field of battle to receive a dispatch requiring an hour for its interpretation. Circumstances ought to guide us in our choice of a rule. Where secrecy is all-essential, and time of little moment, this last condition may therefore be somewhat ignored. We will now take the following as examples of very easy cipher :(1)....Uif beesftt zpv sfrvjsf jt fjhiu Mfx Tusffu. The meaning of which is "The address you require is eight New Street." Here the rule has been to substitute as a symbol for any particular letter the next to it in the alphabet: b has been written for a, ƒ for e, and so on. (2) Uope Idbe ldbmc ftspi. I fwbi uosbfm ubiu fi mmjx fe efiduhsdt. In example (2) the letters are symbolised exactly as in (1); but in addition to this, each word is inverted and must be read backwards. This the reader can decipher for himself. Frequently, however, letters are replaced by others which have no apparent alphabetical connection with them. The Soldier's Pocketbook, by Colonel Wolseley, describes an admirable method of this kind, in which the required substitutions may be at once found on reference to a diagram. The construction of the diagram is readily learnt and remembered by all interested in cipher correspondence, but this is useless in any particular case without a knowledge of the key, which is a word secretly agreed upon by the writer and person addressed. Of course, marks of any kind may be used as symbols, but letters or figures are usually employed. Where a cipher is long enough to include a certain proportion of the letters most commonly in use, or, more correctly speaking, of their symbolical equivalents (supposing each letter to have but one, and the language to be known), its evolution is generally possible by attending to the following considerations as given for the English language in the Encyclopædia Britannica : 1. Letters or symbols of most frequent occurrence may be set down as meaning vowels. Of these, e is the most numerous, u the least so. 2. Vowels most common together are, ae and ou. 3. Consonants most frequent at the end of words are: first, s; next to that, r and t. 4. When a character appears double, it is generally f, l, s, or Vowels e and a. 5. The letter preceding or following two similar characters is either a vowel or 1, m, n, or r. 6. In deciphering begin with words of one letter; they will be a, i, o, or &. 7. Then take those of two letters one of which will be a Vowel. The most frequent in use are: to, be, by, of, on, or, no, as, at, if, in, it, he, me, my, us, we, am. 8. In words of three letters, mostly two are consonants. The most frequent are: the, and, not, but, yet, for, tho', how, why, all, you, she, is, her, our, who, may, can, did, was, are, has, had, let, one, two, six, ten, &c., some of which, and words of two letters, are found in every sentence. 9. Most common words of four letters: this, that, then, thus, with, when, from, here, some, most, none, they, them, whom, mine, your, self, must, will, have, been, were, four, five, nine, &c. 10. Of five letters: their, these, those, which, where, while, since, there, shall, might, could, would, ought, three, seven, eight, &c. 11. Words of two or more syllables frequently begin with double consonants or with a preposition: i. e., a vowel joined with one or more consonants. Most common double consonants: bl, br, dr, fl, fr, gl, gr, ph, pl, pr, sh, sl, sp, st, th, tr, wh, wr, &c. Most common prepositions: com, con, de, dis, ex, im, in, int, mis, per, pre, pro, re, sub, sup, un, &c. 12. Double consonants at the end of a long word are most frequently: ck, ld, If, mn, nd, ng, rl, rm, rp, rt, sm, st, xt, &c. Most common terminations: e, ed, en, er, es, et, ing, ly, son, sion, tion, able, ence, ment, full, less, ness, &c. On principles analogous to these, ciphers written in other languages may (in the majority of cases) be evolved. Many ciphers are rendered more puzzling than they otherwise would be by having the words joined together as though the whole formed one word, and furthermore by the omission of short words such as the, and, &c., the absence of which does not destroy the true sense. The use of capitals may also be dispensed with. But to come to more abstruse systems. If, instead of always representing the same letter by one symbol, we have several, and employ one or other of them ad libitum, the evolution (without the help of a key) becomes extremely difficult, if not practically impossible. The following appears to me a sufficiently easy method of carrying out this principle. Some easily remembered sentence containing every letter of the alphabet, and in which the most common ones are several times repeated, is chosen for a key; the words are lettered in alphabetical rotation, and the letters in each word numbered from the beginning of that word. Suppose, for instance, we take for our key the following sentence, which fulfils these conditions "(a) probity, (b) kindness (c) of (d) manner, (e) intelligence, (f) and (g) zeal (h) for (i) the (j) service, (k) are () qualities (m) which(n) justly (o) excite (p) admiration." To each word an index-letter is affixed, as the reader will observe. The numbering of the letters is not shown-it can be readily obtained by counting. As an aid both in remembering and applying the key, the initial letters of its words, with their index-letters below each, may be kept in a written form always at hand. Thus PKOMIAZFTS AQWJEA a b c d e f g h i j k l m n o p Now, in constructing a cipher, the symbol to be used for a letter is obtained wherever we find that letter in the key, and is formed of the number of the letter in the word containing it attached to the index-letter of that word. As an illustration, suppose we had to cipher "gun," we have but one g, which is the 8th letter in the word "intelligence," whose index-letter is e. For g we therefore write e 8. For u we have two symbols, viz., 12 and n 2, either of which we may employ; and for n eight, viz., b3, b5, đ3, d1, e2, elő, ƒ2, pl0. One form of cipher for "gun is, therefore, e8, n2, d3. Where capitals occur we may use capital index-letters. |