Home Fun

Color Illusions

Most of us know the result of turning a series of circles (as in Fig. 11) horizontally with the eye. The circles appear to revolve rapidly round their center, and in different directions. This is solely because the eyes become confused, giving one more proof, were it needed, that they are no more infallible than anything else on this wide earth.

Some very interesting experiments in color illusions can be made. So cunning is the deception played upon us by our eyes, it is extremely difficult to believe that some of the tints we see in the experiments are but imaginary.

In Fig. 12 you see a top which can be constructed of cardboard in this way. Take a postcard and cut a circle, upon which you draw a diameter as A B. Black the part A C B with India ink, and divide the other half into four equal portions by lightly penciling the radii G E, G D, and G F. Now, still using your India ink, make arcs in these four divisions in the same way as is shown in the figure.

Having done this carefully and rubbed out the pencil radii when the ink has dried, put a pin through the center G from the back, so that the card can easily revolve whilst the pin-head prevents it from falling off. Your color top is now ready. Make it turn rapidly upon the pin; look closely at the card and what do you see? The inner circles become red and the outer ones blue! And yet you know perfectly well that the only colors really upon the card are black and white!

You can make another top, after a similar fashion. Cut your postcard as before, making one half of it black. Now, out of the white side, cut a segment with an angle of 45 degrees, leaving a little piece near the center as shown in Fig. 13. This piece you have left has nothing to do with the effect, but is simply to make the top revolve better.

Take an ordinary book, of which the printing is presumably black, and revolve the top upon the pin at the rate of about five turns a second (a sharp twitch with the finger will do this perfectly well). If you look at the printing now you will find the letters are colored red, as though the book had been printed in red ink!

In both these experiments the alternation of black and white has not only confused the eye, but has deceived it into seeing colors which do not really exist.

So we have shown very conclusively that the old proverb, “all is not gold that glitters,” can be applied to even the plainest of black and white; and, as the poet remarks, “things are not what they seem.”

Therefore, when people wish to impress you with the evidence of their own eyes and clinch an argument by stating that they saw such and such a thing and cannot be wrong, show some of these optical illusions and demand a better proof of what they affirm, very courteously assuring the dogmatist that the best of eyes are liable to make mistakes.

CHAPTER LXIII
CIPHERS AND CRYPTOGRAMS

Successful Systems of Secret Writing

From the earliest times secret writing has been considered no less an art than a necessity. Innumerable have been the systems invented and the means employed to insure the secrecy of messages and instructions. Yet in the passage of time by far the greater number of these methods of cipher has become obsolete and practically useless, failing in most cases to comply with the three great necessities which Bacon declared to be indispensable to all ciphers and cryptograms: (1) Easy of reading and writing; (2) difficult of solution; and (3) void of suspicion.

Ciphers may be generally divided into two branches—code ciphers and letter ciphers. The first of these terms refers to systems so arranged that one group of characters represents several words or sentences, whilst the other term designates those cryptograms where each letter in every word has its corresponding symbol.

As letter ciphers are the more usual, and certainly the handier of the two classes, examples are given of some systems which have been successfully used at different times and for different purposes.

The simplest of all methods, and, for that matter, the easiest to be detected, consists in having an arbitrary list of numbers, one of which shall represent each letter in the alphabet—e.g., A appears as 4, B as 8, C as 12, &c.

This plan can be varied by substituting letters for the numbers, and having each letter of the alphabet represented by another letter—e.g., A being substituted by G, B by L, C by Q, and so on; but the disadvantages attending these very simple ciphers are so great that for a message of any real importance the system is useless.

In the same way the expedient of reversing the alphabet and making A represented by Z, B by Y, C by X, is too simple and generally known to require further description.

One of the easiest and earliest ciphers is shown in Fig. 1. This is written in the following manner: The “bounding” lines in which the desired letters are contained are drawn and the position of the letter in them indicated by a dot. Taking, for example, Fig. 1, A would be one dot, B two, and C three dots inscribed inside the two lines forming the angle. Thus the word CIPHER would be written .

At this point it might be remarked that in all the examples here given the letters are arranged in their simplest order—that of alphabetical sequence; whereas, for practical purposes, they can be arranged in any form desired, the more complicated the better. To illustrate this Fig. 2 shows another arrangement of the letters, by using which the same word would appear .

An example of another simple cipher created merely by the transposition of letters is shown in Fig. 3, which can be read by taking the first letter of the first line, the last letter of the last line, the last letter of the first line, and the first letter of the last, then the last letter of the first line, the penultimate letter of the last, and so on. When the letters in Fig. 3 are properly transposed they will be found to read “A very simple cipher.”

Fig. 3.—Transposition of
letters cipher.

Lord Bacon invented a cipher composed of two letters only, which, although confusing to the uninitiated, is somewhat too cumbersome for any general use. Supposing the two letters decided upon to be A and B, they are grouped into series of five and employed in the following manner: The first letter in the alphabet, A, is represented by AAAAA, B becomes AAAAB, C appears as AAABA, D as AABAA. Using this combination, the same word “cipher” would be written AAABA, BBAAA, BBBBB, AABBA, ABAAA, BBBAB.

Amongst the easy ciphers must be mentioned that shown in Fig. 4, which is used thus: In the center block of small type you find the letters of the word you wish to write in cipher. Suppose it to be TO-MORROW. Now in the vertical column at the side you find that the letter on a line with “t” is A, whilst the letter at the top of the vertical column is G. Therefore the cipher letters for “t” are AG. The next letter, “o,” is on a line with B and under E, so the cipher letters are BE. In a similar way “m” becomes CD, and, proceeding with the remaining letters in the same fashion, we obtain the whole word written in cipher thus: AG, BE, CD, BE, BF, BF, BE, CG.

Russian Nihilist Code

An adaptation of the last-mentioned system is shown in Fig. 5, where the letters at the side and top are replaced by numerals. This method is very much in use amongst the Russian Nihilists, who would therefore write the sentence “Plot discovered” as follows: 41, 32, 35, 45; 14, 24, 44, 13, 35, 51, 15, 43, 15, 14.

This, again, can be very much complicated by multiplying each number by the position held by the letter in the word. Thus in the sentence just put into cipher, P is the first letter in the word “plot,” L is the second, O the third, T the fourth, whilst in the next word D is the first, I the second, &c. You therefore multiply the ciphers in the first word by 1, 2, 3, 4 respectively, and deal similarly with those of the second word. The sentence thus treated would appear—41, 64, 105, 180; 14, 48, 132, 52, 175, 306, 105, 344, 135, 140.

To read this the system must be reversed, and each number divided by its position in the word.

A useful form of musical cipher is shown in Fig. 6, which explains itself. In using this system it is usual to separate the different words by dividing the notes into bars, as can be seen from a glance at Fig. 7. Here it will be noticed that only crotchets and minims are used for ciphers, whilst the other notes introduced have no significance, only serving the purpose of confusing whoever has sufficient curiosity to pry into the message. Therefore, discordant as the passage may sound to the wrong person, it probably makes very sweet music to whoever has ears and eyes to understand its meaning.

Before proceeding to more complicated ciphers, that known as the fractional may be mentioned. This is a very simple method, and easily learned. The letters of the alphabet are divided into groups of five as shown in Fig. 8, each group being marked successively up to five, and each letter in the group treated in the same way. The numerator is used to designate the group to which the letter belongs, whilst the denominator shows the individual letter in that group.

Fig. 8.—The fractional cipher.

Adopting this method the word CIPHER therefore appears as in Fig. 9. As numerals above 5 do not appear in this cipher any more than does the figure 0, they can be added at will to complicate the appearance of the cryptogram, as shown in Fig. 10, where the same word is shown with the addition of meaningless numerals.

The Sphinx

Now to turn to more scientifically constructed ciphers, such as have been employed by various Governments in correspondence with their ambassadors and secret servants.

The Sphinx Cipher, shown in Fig. 11, is based upon a key-word of six or seven letters, previously arranged by the parties concerned A key-alphabet is written in full at the top of the plan, and against each letter of the key-word a complete alphabet is written as shown in the figure.

Fig. 11.—A Government cipher, called the “Sphinx.”

Suppose that the key-word chosen is BALFOUR, and that the message to be sent is WAR DECLARED LEAVE NOW, the key-word is then applied to the message thus:—

You then find in the top row the first letter of your message, which is W, and you see that the letter on a line with B and under W is X, which will be the first letter of your cipher. You then find A above and A by the side, which will give you C. You then find R above, and in the L horizontal column is its equivalent U. Proceeding thus with your message you arrive at the cipher, which reads: XCU HJISBTHH QKHWG QSB.

To read this it is only necessary to write the key-word under the cipher and reverse the proceeding.

An ingenious cipher, used by the War Office of a well-known Continental Power, is partially shown in Fig. 12.

On two adjacent sides of a square entire alphabets are written, commencing at any letter (in the figure they begin at K in one and S in the other). Against each letter of the perpendicular alphabet the entire twenty-six letters are written horizontally, beginning with A and continuing in order. Leaving the first of these horizontal alphabets simple, against the remaining twenty-five, small alphabets are written as you will see in the figure, which shows the plain alphabets and five letters so treated.

Fig. 12.—Another Government cipher—still in use.

The cipher is used in this way. The letters in each word of the message are divided into couples. These couples are found in the doubled alphabets in the center of the cipher scheme, and the key letters at the side and top show the actual cipher equivalent.

Suppose it is desired to put into this cipher the words CABLE CODE. Dividing the letters into couples CA, BL, E. CO, DE are obtained. Finding the combination CA it is simple to ascertain that the index letters are TM, which is therefore the cipher. BL is EL, whilst the remaining letter E from the top alphabet is found to be SO. Treating the word CODE in the same way the ciphers prove to be HM, XN, and therefore the message is transmitted thus: TMELSO HMXN.

So far an idea has been given of the systems of cipher from the simplest methods to the most complicated of political cryptograms. Although the actual details are necessarily hidden, it may be assumed as a positive fact that the most secret political ciphers now in use by civilized Governments are but adaptations of one or other of the methods described.

CHAPTER LXIV
SECRET SIGNS

Friend from Foe

In a condition of affairs where every man’s hand was against his neighbor’s, the necessity of being able to tell friend from foe was more urgent than in these peaceable times.

When plotting was rife upon every hand, and one man possibly held the lives of many confederates in his power, knowing that an incautious word of his might doom them all to punishment and probably death, it became of paramount importance to have some means of discerning allies from enemies.

Obviously the means of finding out such important information must be such as to awaken no suspicion in the event of a mistake, whilst on the other hand there should be no possibility of a stranger inadvertently obtaining possession of the secret.

From earliest times the formation of Secret Societies has necessitated the invention of Secret Signs, and in nine cases out of ten, it may be said, the extinction of the societies from one cause or another has resulted in the loss of their secret signs of recognition.

There are, however, even now, several Societies or Fraternities whose members are possessed of certain signs whereby they can know each other, and in several cases they claim lineal descent from some of the old fraternities whose origins are lost in antiquity.

However, now that universal liberty, especially in this country, has abolished the necessity for concealment, secret political societies have disappeared, and with them their complicated systems of signs, tokens, and pass-words.

In certain colleges and schools societies still exist, and as a secret bond is held by many to be a very effective link in the dearest of friendships, below are given a few suggestions to enable you to invent some secret signs which shall be a tie between yourself and such friends as you may consider worthy of initiation into their meanings.

Like verbs, secret signs may be roughly classed into active and passive. Active signs are those which are given by movements of the limbs or contortions of the face, whilst passive signs are connected entirely with the disposal of parts of the clothing or the wearing of various objects attached to the person.

Amongst active signs, the readiest in execution are those performed by the hands in view of the person, whose attention it is desired to attract, e.g., the signs can be given at the moment of shaking hands, where such a ceremony is observed.

“Shakes” and “Passes”

In this latter case a very good “shake” can be obtained by pressing the thumb firmly against the back of the hand, as shown in Fig. 1. This will arouse no suspicion in anybody ignorant of the meaning, though, if reciprocated, it forms an excellent sign of recognition.

The variety of passes that can be executed with different meanings is astonishing. Yet it should be remembered that, although outsiders may not know what you are saying, it will always be apparent that “something is up,” and a very undesirable curiosity will be awakened.

On the other hand, there are many little actions, unnoticeable in themselves, which may have a great meaning to those “in the know.”

A simple stroking of the eyebrows (Fig. 2) is to all appearances a harmless movement, but in the secret signs of a well-known society it meant that treachery was in the air, and every person in the room would have to be watched.

In a certain Italian Society, clasping the forehead with the left hand as though in extreme weariness (Fig. 3) implied: “Be cautious, you are being watched.” A similar action with the right hand meant: “We are known, make your escape as best you can; leave me alone.”

In the same society, when a member found himself in a mixed assembly, and desired to ascertain who amongst the guests belonged to his fraternity, he would stroke his left cheek thoughtfully with extended first and second fingers, as in Fig. 4.

The brethren of a very respectable society, which still flourishes, are generally credited with knowing each other by a peculiar flourish of the hand when removing the hat, in a somewhat similar manner to that shown in Fig. 5. Others make the ceremony of blowing the nose of like importance.

There used to be a famous Italian Secret Society divided into several classes or degrees, each of which had its own especial sign. For the first three degrees these signs were as follows:—

1st. The right hand is raised to the shoulder, and then passed slowly down across the body to the left knee.

2nd. The right hand is placed upon the left shoulder, then drawn slowly down the left arm until it reaches the hand. Thus clasped they are raised to the breast.

3rd. The right hand is clasped, the thumb and little finger extended. The former is placed against the lips, whilst the latter touches the breast.

Those who desire to invent secret signs should avoid all those dependent upon an unnecessary action, like the hat-flourish. It is more satisfactory to apply the secret to some everyday action which, from its very unobtrusiveness, will attract the attention of no stranger.

Members of certain religious secret societies to this day distinguish one another by a peculiar style of cross, worn as a pendant from the watch-chain, whilst a pass-word is current amongst them to enable them to test those whom they meet wearing the symbol.

The use of flowers in the button-hole is a very common method of attracting recognition, whilst a development of the same idea is seen in the wearing of different colored neckties or ribbons, which in a crowd will pass unnoticed save by those whose attention is desired. Yet to both of these systems a certain danger is attached, for there is always the chance of some unsuspecting person quite inadvertently wearing the same flowers or colors.

Every one has heard of the language of flowers, but it is surprising to what an extent this can be carried by enterprising young ladies with a good collection in the garden or green house.

It has been frequently proved that some safeguard is a necessary addition to the sign, and this safeguard usually takes the form of a pass-word. Repeated after the sign has been given, this word serves to show that the secret sign was neither given by accident nor picked up through curiosity.

Pass-Words

Pass-words, and the methods of giving them, vary considerably. The word, which must of course be known to all duly intrusted with the secret, should be of two syllables.

One party called A says the first syllable, and the other person B repeats the second, then saying the whole word. Supposing the pass-word chosen be Oxford, A would make some remark introducing the word Ox, whilst B, replying in a similar vein, would mention the last syllable “ford” and conclude by repeating the whole word. With this system it is almost impossible for an outsider to palm himself off as one of the elect, even if he has become acquainted with all the signs of the society.

It is a well-known fact that gypsies have a concerted plan of signals which are employed to show members of the party the direction taken by their leaders.

The “Patteran”

The “patteran,” as it is called, is made in various ways. A piece of rag fluttering from some bush near a cross-road, is a favorite signal, whilst small twigs or leaves strewn in a particular direction, have a somewhat similar meaning.

Tramps and vagrants of all kinds have a series of signs, which they chalk upon the walls of the various houses at which they call, serving to inform their brethren of the treatment received at the hands of the occupiers.

By this method a rude cross will usually describe the rather chilling welcome offered them by an irate householder, whilst a rough sketch of a loaf of bread shows that the inmates are sufficiently sympathetic to dispense with a portion of “the staff of life.” On the other hand, an upraised leg with a boot upon its foot tells a tale which need not be further enlarged upon.

As to the various modes of recognition that can be produced by whistles and cries of all kinds, they are too familiar to require description in these pages.

CHAPTER LXV
GAMES AND AMUSEMENTS FOR THE BLIND

The Wonderful Sense of Touch

It cannot fail to strike those of us who are blessed with the use of our eyes how extremely fortunate it is that our blind friends need not be debarred from many of our games. Being deprived of their sight, their sense of touch is developed to such an incredible extent that in the playing of many games their fingers prove of the same use to them as our eyes do to us.

Practically all games for the blind can be purchased at very moderate cost, yet as they can be quite easily made at home the following hints are offered in the hope that they will prove of use, and help some of our readers to entertain a friend less fortunate than themselves.

Cards

An ordinary pack of cards can be very simply adapted to the use of the blind.