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WRITING BY TELEGRAPH.
ALMOST every one, at some time or other, has written letters of light on the wall of his room by means of a piece of looking-glass, upon which the sunlight was allowed to fall. Imagine yourself, says the Paris correspondent of the Amsterdammer (Amsterdam), now to have such a piece of glass in the hand, and that the light of the sun or of a lamp is reflected from this upon the wall. If the hand be kept still the reflection on the wall remains stationary. If the glass be bent forward a line of light will be projected downward upon the wall; if pushed to the right the line will move toward the left.
Now, instead of being held in the hand, let the piece of glass be fixed at a certain point so that by means of small movable rods the forward bending and the same movement to the right can be produced with their corresponding effect in the reflections. Any one can see now that it depends only upon the guiding and directing power by which the two rods are moved simultaneously to cause the reflecting glass to write letters upon the opposite wall. And any one can see, also, that by keeping these rods in contact with two telephone wires along which an electric current can be conducted, a mirror
placed, say, at Amsterdam, might be so moved from New York as to write letters upon a wall in the former city.
After stating that the inventor of the socalled "word photography," Dr. Marage, modestly affirmed that his invention was based largely upon the previous invention of telegraphic writing by Pollák and Virág, the writer proceeds:
The invention of Messrs. Pollák and Virág consists of two sets of apparatus, one, let us say, placed at New York, whence to send the two necessary electric currents; the other in Amsterdam, in order, by means of these currents there received, to write characters. The receiv
ing apparatus, placed at Amsterdam, consists of a camera obscura, in which are found, at the point where otherwise the lens is placed, the mirror, which can be moved from New York in any direction; at the opposite side, in the usual place in a photographic apparatus, a tightly stretched sensitive paper that can be indefinitely rolled off; below, and between these two, some body capable of giving a powerful light.
A word as to this light-source: That the mirror might not write all the characters on the same spot, the inventors had to discover a means by which from this light, via the mirror, a reflection could be cast which would move constantly along the sensitive paper from left to right, as the hand moves in writing. This result they obtained by
within a larger copper tube which in its circumference has one spiral-formed groove. On turning this copper tube, or cylinder, a ray of light falls upon the mirror from a point lying more toward the side. So that, whenever the mirror is not moved, but the sensitive paper is rolled off and the copper tube turned, a series of lines are formed on the sensitive paper running from left to right. If, at the same time, the mirror is made to move in the required manner, these lines are changed into words, and the apparatus writes entire sentences.
The utility of this invention is shown by the writer's description of the apparatus which transmits the electric current, and which he supposes to be placed at some point in New York.
This apparatus consists of a metal cylindrical drum, through which is carried an electric current. Over this drum runs a strip of parchment paper, profusely perforated, through which perforations the electric current can be made to run to the teeth of a metal comb, pressing firmly upon the paper the conductors of the freed current from the two telegraph wires.
Messrs. Pollák and Virág have invented a perforating machine which vastly increases the rapidity in working the telegraphic inWith their system it has been demonstrated that, when the parchment strip is ready, from 32,000 to 50,000 words per hour can be transmitted, while the most rapid system of telegraphy, the Wheatstone, only reached 18,000 per hour. These parchment paper strips can be prepared in the telegraph office by twenty or thirty employees at once, each taking charge of a part of the telegrams; in commercial houses, government bureaus, etc., where, instead of writing down with a pen or typewriting a telegram, it is perforated on the strip. A mercantile house or a newspaper which should hold two telegraph wires of this system for five minutes could in that space of time send along the two wires 2800 words.
Upon this invention, Dr. Marage has based his own invention for the production of the "photographic word." In his apparatus the mirror, instead of being brought into correspondence with two electric currents, is put into connection with a telephone membrane, the vibrations of which are reproduced graphically upon the sensitive paper.
This invention is now being developed by electrical experts everywhere. Already por
ELECTRIC WAVES AND WIRELESS TELEGRAPHY..
or ethereal, telegraphy is the newest invention of modern physicists. Marconi is generally credited with the first practical illustration of its wonders, although it is quite clear to scientists that many years before Marconi received a wireless message, in 1902, while on the Atlantic, which had been transmitted from his station at Poldhu, Cornwall, Faraday, Clerk Maxwell and Hertz had been experimenting for years with "electric waves.' Heinrich Hertz was the first to recognize an electric wave, and the first to construct an instrument to detect it. Essentially, there is no difference between electric waves and light waves. Size is the only distinction. Light waves are so small that many thousands can be packed within the compass of a single inch, while electric waves are so big they may be feet, miles, or even thousands of miles in length. The visual eye is responsive to the small waves but not to the big waves. To recognize them Hertz invented a special instrument.
Newton taught that every self-luminous body emits minute material particles which cause the sensation of light when they fall upon the retina, which is called the "emission theory." Modern scientists hold that light and radiant heat consist of waves in ether. This is termed the wave, or undulatory, theory. Light waves can be reflected, refracted, and polarized, and Hertz established the same properties in invisible electric In the course of his experiments Hertz made the notable discovery that, unlike the more familiar visible waves of light, electric waves pass freely through doors, wooden floors, and even through stone walls and masses of pitch of great thickness, though all these things are practically impenetrable to light. This he established by means of an oscillator and a receiver. These instruments were sixteen or seventeen yards apart and separated by closed doors and, at times, by stone walls. Attached to these were automatic galvanic batteries, and at each oscillation a wave was generated which traveled with the velocity of light to the distant receiver, which was perfectly syntonized. This is the gist of the art of wireless telegraphy: producing electric waves similar to light waves, and detecting them at a distance by means of a tuned or syntonized" receiver. Mr. W. A. Shenstone, F.R.S., contributes to the Cornhill Magazine for March an exceedingly interesting paper on this subject.
"I need hardly say that it is one thing to detect an electric wave fifteen or twenty yards away from its point of origin," says he, "and quite another thing to detect it after it has traveled scores or perhaps hundreds of miles over land or sea; and when this is done there remain two difficult problems: First, to make the wave print the message it carries in black and white for our eyes to see; and, secondly, to secure that the message shall go into the hands intended to receive it and into no others." Progress in this direction has been greatly stimulated by discoveries of Duddell and Poulsen, the latter an eminent Danish physicist. The former contrived to subject the familiar "electric arc" to perfect control, and the latter, by subjecting it to a powerful magnet, at the same time lengthening it and surrounding it with an atmosphere of the light gas hydrogen, increased the frequency of its oscillations to a million per second.
"6 ADVANTAGES OF ARC TELEGRAPHY." Commenting on this remarkable achievement, Mr. Shenstone says:
If Mr. Poulsen's "arc telegraph" can be made a commercial success it may be expected to secure the following advantages: First, greatly increased accuracy in the tuning or syntonizing of transmitters and receivers. This will make it comparatively easy for neighboring stations to avoid interfering with each other's messages and will get rid of, or at any rate mitigate, one of the difficulties which have helped to bring about the need for international conferences and agreements. Secondly, there is good reason to expect that if "arc telegraphy" should replace
spark telegraphy the energy required for transmitting a message, and therefore its cost. advantages can hardly fail to make easier the will be considerably reduced. These combined realization of that scheme of transatlantic communication, which so often has seemed on the very verge of success, and so often has resulted only in disappointment.
waves in the ether, and these, traveling with the velocity of light, reached the receiving station in about the one two-thousandth part of a second. Here, falling upon a second aërial," these waves set up oscillations in the primary wire of a receiving coil; these, in their turn, set up yet fresh oscillations in the secondary wire of the coil, which broke down the resistance of the coherer and started into action a Morse
ing key was pressed, and sparks passed across
GOOD EYESIGHT AND GOOD HEALTH.
School life, Dr. Gulick contends, is responsible for deformities of the eye, and he startlingly declares that, approximately, onethird of all the children in the upper grades
HIGH medical authority asserts that probably one-fourth of all the educated people in America suffer from various kinds of disturbances more or less due to eyestrain, and refers to Carlyle, Huxley, and Wagner, of the elementary schools have eyes that as victims through this cause. Headache, rather seriously need correction by means of backache, indigestion, hysteria, and even spectacles. In cases of headache, backache, epileptic seizures have been cured by the use interferences with digestion, and nervous exof spectacles! Strange though it may seem, haustion, when the symptoms are not cleara strain upon the small optic muscles is capa- ly traceable, the eyes should be examined, ble of seriously disturbing our whole organ- because they are peculiarly vulnerable, and, ism, because of the relation between them hence, must be suspected. and vital parts of the human machine.
To overcome, or, at least, to minimize the evil effect of reading in street cars, he makes two practical suggestions: (1) Select for reading only books or magazines with clear type, good margins, and lines sufficiently short and far apart so that when the eye travels from the end of one line to the beginning of the next it will not be apt to fall on the wrong place; (2) select reading matter that requires more study than reading,-books that require deliberation, reflection, thinking. Newspaper type is hurtful, but if we must read on the cars, a good plan to relieve the strain is to look up and off for a moment every little while." Women who read through veils when traveling should give up either the reading or the veils.
Adjusted to outdoor light, which is reflected light, our eyes are injured by direct light. Hence, we should avoid reading or working in a position where a bright light shines directly into the eyes. The pupil of the eye admits light in proportion to the general illumination when that is reflected, but cannot contract sufficiently when subjected to one irritating stream of direct light. Lights in a room should be thrown on the ceiling first and reflected therefrom. Light is never safe nor pleasant when one can see its source; hence, when electric bulbs are used, the carbons should not be visible. Bathing the eyes with cold water will greatly relieve
"The pictures that are made in our eyes," says Dr. Luther H. Gulick, director of physical training in the New York public schools, in the World's Work for March, "and that are always being translated into nerve currents and reported to the brain, form the foundation for our thinking. They constitute a far larger factor of the brain than the mere size of the muscles involved would indicate, that is, vision is a fundamental activity, and, by interfering with it, many of the other organisms are disturbed. Constant exhaustion and strain of these visual centers will frequently cause disturbances of the most extensive character." This follows because the strain of civilization rests heavier upon the eyes than upon any other organ. The savage does not experience this, because his eyes are used differently. He merely looks at things, near or far; the modern man not only looks, but also reads, and the deterioration of the civilized eye is due to the constant endeavor to distinguish small black marks on white paper. Another difference between the civilized and savage use of the eye: The civilized eye is accustomed to regard things at intervals at long and short range; the savage, usually, enjoys a long focus. The constant employment of the short focus of 15 to 18 inches, by the house-living man, and the occasional use of the long focus of the
procure glasses properly adjusted. In con- body. People with weak eyes will be far more clusion, he says:
Disorders of the eyes not merely affect the rest of the body, but the eyes themselves in many cases act as a sensitive barometer with reference to the conditions of the rest of the
apt to have eye-pains when they are suffering from indigestion or overwork than when normal conditions of health obtain. . . . Therefore it is most important that people who experience difficulties with their eyes should keep themselves in good general health.
TRACES OF HUMOR IN
HIS most unusual topic is treated at some length in the March number of the Biblical World (University of Chicago). The writer of the article, the Rev. Shepherd Knapp, of New York City, finds it almost necessary to apologize for dealing with a theme that has so seldom been. discussed by theologians. As he remarks at the outset, to the great mass of Christians it has not even occurred to ask whether Jesus had a sense of humor or not. By many the question, even if raised, would be at once dismissed as trifling or, perhaps, irreverent. This writer, however, enrolls himself among those who think that a sense of humor is a very marked addition to the human character, and who would feel that the life of Jesus was unhappily limited and incomplete if it was all somber and strenuous."
It should be understood that the word humor is used by Mr. Knapp in a very general sense, including any expression of amusement, any form of pleasantry, any apparent conception of the ludicrous in action or situation or idea, in short, any genial exercise of imagination. Several characteristics of the recorded words of Jesus would seem to make his possession of a sense of humor quite probable. Imagination, the chief essential of humor, was in him highly developed. He spoke in parables, metaphors, and similes, so that his collected sayings are like a sort of moving picture. Attention is also directed to the homeliness in many of his imaginative expressions that would provide "excellent raw material for humor when needed." These traits, taken together with that quickness of action and conversation of which a good example is the use by Jesus of the image and superscription on the penny when asked about the lawfulness of giving tribute, go to show that the possession of the sense of humor would not be in any way unnatural or abnormal in such a character.
Humor as an element in Christ's sayings is to be looked for in two different forms: On the one hand, it may be literary in character, dependent on the contrast of ideas put
THE SAYINGS OF JESUS.
forth by the speaker, or on his manner of describing persons or events. On the other, it may be humor of situation, dependent upon a relation between the words spoken and that which is going on at the time of their utterance, especially in the minds of the listeners.
Of the literary humor Mr. Knapp finds the clearest examples in Christ's words in the form of exaggeration. The parable of the mote and the beam (Matt. 7:4) is a famous instance.
A more elaborate instance of literary humor is the delightful little glimpse that Jesus gives us of children at their games in the marketdance; we wailed and ye did not mourn" place: "We piped unto you and ye did not (Matt. 11:17). It is the last clause that causes or ought to cause a smile: We wailed and ye or, more literally, "did not did not mourn," beat your breasts." Read this seriously, and you have before you an inexplicable group of people, manifestly grown up,-not children at all-who solemnly charge one another with lack of sympathy. But the scene that Jesus really drew was what a modern child would call playing funeral"; only in the Palestine of Jesus' day the customs of mourning offered a much more fertile field for the heartless imitation of children than is the case with us. "Don't you know," says one child to the other,
that unless you beat your breast when I begin to wail, you spoil the whole game?" I think this passage alone would assure us that Jesus was not ignorant of the manner in which humor may be put to use.
The one remaining instance of this literary humor that I shall produce is also an illustration of the fact that the humor in Christ's sayings is sometimes so plain as barely to need to be pointed out. In the parable of the Excuses (Luke 14:16-23) I suppose that the pleas offered by the three men for not attending the great supper to which they had been invited, struck many of us as distinctly funny; they and especially that of the last one, have often seem so much like the modern attempts to get out of an inconvenient engagement: I have bought a field and must needs go and see it"; "I have bought five yoke of oxen and I go to prove them"; "I have married a wife and therefore I cannot come." All this we should be sure was humorous if it was not in the gospel. But it is humorous, whether in the gospel or out of it. For my part, I have at least little doubt that, when Jesus first made this graphic reference to the much-married man, some one among the auditors, who was known to walk
in matrimonial leading-strings, was nudged or clapped on the back by his companions.
(Luke 14:7-24). In the latter passage it is noted that single phrases and terms of expression betray a humorous vein, as when Christ says: In giving a dinner or a supper do not invite your friends or your brethren or your rich neighbors, lest haply they bid. you again" (Luke 14:12). Similar in
Of the second group of illustrations, the instances of humorous situations arising from Christ's words, Mr. Knapp cites the parables of the patched garment and the new wine in old wine-skins (Mark 2:21 f.), and the discourse at the chief Pharisee's table stances might be multiplied.
BRAIN-WEIGHT AND INTELLIGENCE.
dying at 65 years of age, showed a brainweight of 2012 g., while Walt Whitman, who died at 72, had a brain-weight of 1282 g.
IT is impossible to conceive of many of our psychic manifestations except as associated with special organs of the body. For instance, the simple sensation of sight is possible only when a certain definite part of the It is extremely difficult to get data for brain,-i.e., the occipital lobes,-is in a nor- studying the relation between brain-weight mal condition. Many instances of this sort and intelligence in normally intelligent men give evidence that a part, at least, of our on account of the obstacles in the way of psychic manifestations are bound up with examining brains, due to the inherent prejuprocesses whose course runs parallel with dice against such treatment of the dead. certain bodily developments, and doubtless The same methods have been used in our constantly increasing knowledge of the the attempt to discover whether the brain science of physiological psychology will dis- is different in primitive and in cultured close many more relations of this sort than are yet known.
The very interesting question arises as to the relation between mind and matter, between the intangible and the tangible, the possibilities of which have never yet been fully exploited.
Whether there is a relation between unusual brain-weight and exceptional intelligence, and to what extent such a relation may exist, are questions as interesting as they are difficult to answer.
Dr. Johannes Dräseke writes on the subject in the last number of the Archiv für Rassen- und Gesellschaft-Biologie (Berlin). Have the marked intellectual power of noted men been correlated with the increased metabolic activity of an unusually large brain mass? Study of the brains themselves ought to give direct evidence on the question, and with this end in view the writer ascertained the weights of the brains of a large number of famous men.
Thackeray is cited as dying at the age of 52, and having a brain weight of 1658 g.; Helmholtz, the noted physicist of Berlin, who died at 73, had a brain-weight of 1420 g., the same as that of Schubert, the musical composer, who died at 31. Goltz, a leading physiologist, died at 68, and had a brainweight of 1395 g. Louis Agassiz, the naturalist, had a brain-weight of 1495 g. at the
A Russian surgeon weighed the brains of 500 Slavs, and found the average weight to be 1409 g., comparing favorably with the brain-weights given of famous men.
Although the natives of Tierra del Fuego are considered as belonging to one of the lowest races of mankind, two brains examined showed no lower structure than brains of other races, and the one brain-weight given of this race was 1403 g. Examination of a Papuan brain showed nothing in the system of convolutions and sulci that was in the slightest degree different from the European brain. There was a suspicion that these brains had undergone some change before they were examined, on account of the readiness with which nerve tissue absorbs moisture and so increases in weight.
On the whole, it seems probable that there is a relation between higher intelligence and increased brain-weight, although it is difficult to determine just how closely the two are correlated, for the fact must not be lost sight of that a great part of the energy of the brain must be spent in controlling growth and the vital activities of the body, as well as the infinite variety of muscular movements. Further disturbing factors enter into the problem from the uncertain matter as to what proportion of the brain is active nerve substance and what part is inactive tissue serving to