More Science From an Easy Chair

a photographic plate), and gradually became familiar to everyone in the exhibitions known as the "biograph" or "cinematograph," the actual position of th

ons of the legs "must" be, by studying the hoof-marks in a soft

ture is usually also about one-thirtieth of a second, so that at least fifteen pictures are taken in every second of time, and according to the requirements of illumination and the rapidity of the movements of the men or animals photographed this number may be greatly increased. The film is developed, printed and fixed on a similar rolling mechanism and the pictures are thrown one by one by a powerful lantern on to a screen, and are jerked along at the same rate as that at which they were taken, and are magnified enormously. Animals and men in rapid movement, railway trains, the waves of the sea are thus ph

ext by an interval of one fortieth of a second. The horse in Fig. 10 has returned to the same pose as that with which the series starts in Fig. 1. Fig. 11 gives a pose one hundredth of a second ea

c shutter-openers, a side, a back, and a front view of the animal were taken simultaneously. Repeated photographs were obtained at intervals of a fraction of a second, giving a series of fifteen or twenty pictures of the moving animal. The length of exposure for each picture was one-fortieth of a second or less, and the interval between successive pictures was about the same. Muybridge's great difficulty had been to invent a shutter which would act rapidly enough. I have some of these pictures before me now (see Pl. I). They show that what has been drawn by artists and called the "flying gallop," in which the legs are fully extended and all the feet are off the ground, with the hind hoofs turned upwards, never occurs at all in the galloping horse, nor anything in the least like it. There is a fraction of a second when all four legs of the galloping horse are off the ground, but they are not then extended, but, on the contrary, are drawn, the hind ones forward and the front ones backward, under the horses' belly (see Pl. I, figs. 2 and 3). A model showing this actualinstantaneous attitude of the galloping horse has recently been placed in the Natural History Museum. When the hoofs touch the ground again after this instantaneous lifting and bending of the legs under the horse, the first to touch it is that of one of the hind legs (Pl. I, fig. 4), which is pushed very far

f the Black Sea, dating from 500 b.c. Fig. 5.-From Muybridge's instantaneous photograph of a fox-terrier, showing the probable origin of the pose of the "flying gallop" transferred from the dog to other animals by the Mycen?ans.

igs. 2, 4 and 5 of Pl. II. Fig. 3.-From a Japanese drawing of the seventeenth century; the pose is a modification of the "flying gallop," and agrees closely with that of Fig. 1 in this plate. Fig. 4.-The flex-legged prance from a bas-relief in the frieze of the Parthenon, b.c. 300. Fig. 5.-A modern French

mit that the true instantaneous phases of the horse's gallop (or of any other very rapid movement of anything) cannot be seen separately by the human eye, but can only be separated by instantaneous photography, ought an artist to introduce into a picture, which is not intended to serve merely as a scientific diagram, an appearance which has no actual existence so far as his or other human eyes are concer

t up to the end of the eighteenth century "the flying gallop" does not appear at all! The first example (so far as those schools are concerned) is an engraving by G. T. Stubbs in 1794 of a horse called "Baronet." The essential points about "the flying gallop" are that the fore-limbs are fully stretched forward, the hind limbs fully stretched backward, and th

r date than that in which he introduced "the flying gallop." The "stretched-leg prance" is found in Egyptian works (Pl. II, fig. 8) of 580 b.c., and is a favourite pose to indicate the gallop, in ancient Assyrian as well as medi?val art, for instance, in the Bayeux tapestry (Pl. II, fig. 6). We find, further, (2) that the second pose made use of for this purpose is the "flexed-leg prance," in which all the four legs are flexed, so that the hind legs rest on the ground beneath the horse's body, whilst the forelegs "paw" the air. This is seen both in Egyptian, Greek, and Renaissance art (Leonardo, Raphael, and Velasquez)

r's time (800 b.c.). Europe never received it, nor did the Assyrians nor the Egyptians. Thirty centuries and more separate the reappearance in Europe of the flying gallop-through Stubbs-from the only other European examples of it-the Mycen?an. What, then, had become of it, and how did it come to England? M. Reinach shows, by actual specimens of art-work, that the Mycen?an art tradition, and with it the "flying gallop," passed slowly through Asia Minor north eastwards to the Trans-caucasus (Koban, 500 b.c.), to Northern Persia, and thence by Southern Siberia to the Chinese Empire (Pl. III, fig. 2) as early as 150 b.c., and that the "flying gallop," so to speak, "flourished" there for centuries, and was transmitted by the Chinese artists to the Japanese, in whose drawings it is frequent (Pl. III, fig. 3). It was at last finally brought back to Eur

he "flying gallop" was devised as an intentional expression of energy in movement. I venture to hold the opinion that it was observed by the Mycen?ans in the dog, in which Muybridge's photographs (now before me) demonstrate that it occurs regularly as an attitude of that animal's quickest pace or gallop (see fig. 5, Pl. II). It is easy to see the "flying gallop" in the case of the dog, since the dog does not travel so fast as the galloping horse, and can be more readily brought under accurate vision on account of its smaller size. The late Professor M

eece, and their successors in Europe as an expedient without conviction, to represent rapid movement, the true poses of which defied satisfactory reproduction. And it is also the fact that the "flying gallop," which appeared in Mycen?an art thirty-seven centuries ago, and then travelled by a "Scythian" route through Tartary to China, and came back to Europe at the end of the eighteenth century, is also-so far as it has any real representative in the action of the horse-only approached by a brief phase of the "jump." The poses of the horse in jumping are shown in the small figures taken from instantaneous photographs and reproduced in Fig. 6 of Pl. III. The "flying gallop" ("ventre a terre"), with all four legs stretched, and

ke the instantaneous photographs, his object being to show what "is," and not what the artist aims at, namely, what "appears," "seems," or (without pondering and analysis) "is thought to be." The painter, in his quality of artist, would be wrong to select any one of the dozen or more poses of the galloping horse published by Muybridge, each limited to the fortieth of a second, since no human eye can fix (as the photographic camera can) separate pictures following one another at the rate of twenty a second, each

fortieth of a second-but as a blurred haze of some fifty or more indistinct "spokes." In this case it undoubtedly results that the observer of the picture is satisfied and receives the mental impression or illusion of a rapid rotation of the wheel. I have tried the experiment with instantaneous photographs of the galloping horse, and I get three results: first, no combination of successive phases occupying one-tenth of a second gives anything resembling the "flying gallop" of the racing plates (the Mycen?an and Stubbsian pose), or

ive an account of the scene that was pictured on the back of his eye. Attention, the direction of the mind to the sensation, is necessary; and it appears that it is very difficult (to some more than to others) to hold the attention alert, and to give it to the unexpected. In fact, to a very large extent we can only "see" (using the word to signify the ultimate mental condition) that which we are prepared to see or that which we expect to see. In the absence of such expectation, a very strongly illuminated or well-marked, outstanding object is far more readily "seen" than less marked objects. Accordingly, the outstretched legs of the galloping horse, now in front and now behind, are "seen," whilst the rest of the phases are not observed. Moreover, it is a fact that the swinging pendulum of a clock is "seen" at the extreme position of the swing on each side, an

forward pose of the galloping horse's front legs and the most backward pose of its hind legs-though far from simultaneous, even in the slow changing retinal impressions-may be mentally combined by "the arrest of attention," and that the artist really ought to present his picture of the galloping horse with those two poses combined (although as a matter of scient

allops. The mind revolts at such a presentation, though it is true, and the whole scheme and composition of the artist is perverted or fails to gain attention and to exercise its charm-by the unwelcome presence in his picture of the revolting truth. It is the consideration of facts of this kind which enables us to understand the origin and importance of what are called "conventions" in pictorial or glyptic art. The artist is, in fact, operating by means of his painted canvas or moulded clay upon a queer, prejudiced, ill-seeing, dull, living creature-his brother-man. In order to give if possible to that brother, by means of a painted sheet, some or all of the delights, emotions, suggestions, perceptions of beauty, and so on, which he himself has experienced in contemplating a re

imitations (but not all-certainly not that of Stubbs, of the Epsom Derby of Géricault, and the racing plates) seem to me to be eminently satisfactory and successful in this respect. In the pictures to which I allude (Pl. III, figs. 3 and 5) all the legs are off the ground; the front legs are advanced, but one or both may be more or less flexed, whilst the hind legs, though directed backwards with upturned hoofs, are not nearly horizontal (as they actually

uration than the poses of the gallop, can only be correctly estimated by the eye with great difficulty, and only sketched by artists of exceptional skill and patience. The movement of the wings of birds in flight has been very successfully analysed by instantaneous photography. Some of the poses revealed must familiarise the public with what can be, a

Desert, in Central Asia. This horse is known as Prevalsky's wild horse, in honour of the Russian traveller who discovered it. Live specimens are now to be seen in the Zoological Gardens and elsewhere. It closely resembles the drawings of horses made by the pal?olithic Cromagnard cave-men. A century ago a wild horse, probably of the same race as this, inhabited the Kirghiz Steppes, and was known as the Tarpan: it is now extinct. The more southern Arabian horse is not known in the wil

the giraffe. It is often exhibited by the giraffes in the Zoological Gardens in London, but has not, I believe, been recorded by a series of instantaneous photographs. When going at full speed over the grass wilds of Central Africa the giraffe exhibits a gait more like the galloping of deer and antelopes, and carries

arks. Thus, a rifle bullet is readily photographed while in flight with scarcely perceptible distortion. A wheel revolving many hundred times a second can thus be photographed, and appears to be stationary. Dr. Schillings has applied this method to the photography of wild animals by night in the forests of tropical Africa, and has published an interesting book giving his photographic results. In order to take these pictures the trac

this way-lions and leopards advancing on their prey were suddenly revealed, and the helpless a

le succeeds in turning itself so as to alight on its feet. During a fall of less than 3 feet he obtained five successive spark-pictur

the shutter is open and travel when it is shut, has been applied to the analysis of other movements than those I have mentioned, and has yet to be applied to many more, such as the crawling of insects and millipedes, and the beautiful rippling

t walking rapidly, and suddenly turns to the right or left. A fraction of a second occurs when the toes of the two feet are directed towards one another (that is to say, are "turned in"), as one of the legs swings round in the break-off to right or left. This instantaneous phase is very awkward and ugly in appearance. It is never pictured by artists, although reg

a second this gives place to a dawning smile, which as we pass along two or three later "instantanèes" develops into a broad grin of satisfaction. Another genuine study of expression both of face and gesture and movement is given in the series where a pailful of cold water is unexpectedly poured over the back of a bather seated in a sitz bath-astonishment, dismay, anger, eagerness to escape, and the reaction to shock are all clearly shown. Darwin's studies on "the expression of the emotions" would have been greatly assisted by such analysis, and the subject might even now be developed by the use of serial

n it is low down near the horizon than when it is high up, more nearly overhead. Of course, no one nowadays imagines that the moon or the sun swells as it sinks or diminishes in volume as it rises. Those who think about it at all, say that the greater length of atmosphere through which one sees the low sun or moon, as compared with the high, magnifies the disc as a lens might do. This, however, is not the case. If we take a photograph of the moon when low and another with the same instrument and the same focus when it is high, we find that the celestial disc produces on the plate (as it does on our eyes) a picture-disc of practically the same size in both positions. In fact, the hi

tered by the moon's disc is probably due to a little distortion caused by the side portion of the lens. After M. Flammarion. The actual width of the moon's disc as printed here is a little over one eighth of an inch, which, if we regard it as "a picture" and not mer

-so long as the same "eye-to-frame" or "peep-hole" distance is preserved. That seems to be an important fact for painters of sun-sets and moon-rises. But what do they do? They never give the right size (namely one-sixth of an inch) which corresponds to an eye-to-frame distance of eighteen inches. They give to a high moon, if they are very careful, a quarter of an inch for diameter. This means that the observer is about two and a half feet, or thirty inches from the picture-nearly twice what the artist's eye really is as he paints. And then-if painting a moon-rise or sunset-they suddenly pretend to go to a distance of nine and a half feet from the picture and make the moon an inch across because it is low down, or even give the moon two inches in diameter, which would mean that they (and those who look at the picture when hung up for view) are observing at nineteen feet distance from the front plane or frame of the picture. They do not alter the other features in the picture to suit this change of distance of the eye from the frame and there is no warning given. Certainly there is no obvious and necessary reason for treating a picture containing a high moon as though you were three feet from the front plane of the scene presented, and a low moon as though you were twenty feet from that plane! The confusion which may result in the representation of other objects when these changes of eye-to-frame distance are made is shown by the following simple facts. According to the simple laws of perspective, if the eye is at

e same size. This is, I believe, the correct explanation of the illusion. When one gazes upwards to the sky, a small insect slowly flying across the line of sight sometimes is "judged of" as a huge bird-an eagle or a vulture-since we refer it to a distance at which birds fly and not to the shorter distance to which insects approach us. It seems that it would be possible for the painter, by carefully studying actual natural facts and introducing their presentation into his picture, to produce the impression of greater distance, and therefore of size, into a quarter-inch moon placed near the horizon. He is not compelled for want of other means to "cut the difficulty" and paint a falsely inflated moon which shall brutally and by measurement call up the illusion of increased size. I reproduce here (Pl. V) an interesting drawing which shows how such illusions of size can be produced. It is none the worse for my purpose because it is an advertisement by the well-known fi

et owing to the position in which the three figures are placed and the converging lines-suggesting perspective-the drawing of Mr. Asquith does not merely represent a much taller man than does that of Lord Lansdowne, but actually gives the impression, at first sight, that the

inated disc of one foot in diameter, it will, when looked at at a distance of 115 feet, have the same visual size as the moon itself, but if your seat is nearer the scene it will look too large, if further off it will look too small. There is no getting over this difficulty, as the standard of actual Natu

the sense of beauty, to emotion, and sentiment. Approved departures by the artist from scientific truth are those which are deliberately made in order to give emphasis-as, for instance, in the huge, but tender hand of the man in the emotional masterpiece, "Le Baiser," by t

nd criticism. It is possible for a landscape painter to improve in his treatment of the moon by better observation and increased knowledge-just as other painters have learnt

note on

l'art ancien et moderne," 'Revue Arch

? How soon must it be followed by another stimulus (another image) so that there may be fusion or continuity, the one succeeding the other before the earlier has had time, not to disappear, but to decline. If it has had time to decline in intensity, the appearance of flickering results. That is what the cinematographer has to avoid. It is found that a quicker succession-a shorter interval-is necessary with strong light than with weaker light in order to pr

m us-very nearly the same as that of the moon-and is subject to the same numerical law of apparent diameter, viz. a disc of an