The Stereographs — How to Use Them

( Originally Published 1907 )

These stereographs are not mere "pictures" of Norway. They are much more than that. The two prints mounted side by side are not alike, though they seem alike to the unaided eye. They were made from two different negatives, which in turn had been produced by two different lenses, though their exposure was made at the same instant. The two lenses were set side by side in a binocular or "stereoscopic" camera, i. e., a camera whose lenses act like the two eyes of a human observer. The ordinary camera works only as a one-eyed man would see.

But a man's two eyes give him knowledge far beyond what he could get from one eye alone. There is good reason why Nature should equip him with two eyes rather than one, though he is seldom conscious of the reason.

Experiment for yourself to see the difference between the reports given by your right eye and by your left eye. Hold your right arm out straight be-fore you at full length, the open palm toward the left. Close your left eye and look with the right eye alone. You see the edge of the hand and a little of the back of the hand.

Keep the arm in exactly the same position. Close the right eye and look only with the left eye. You see now the edge of the hand and a little of the palm, but not the back.

Look with both eyes at once. You see now the edge of the hand, a part of the back and at the same time a part of the palm—in fact, you see part way around the hand. Your eyes tell you that the hand is a solid, substantial thing, with length and width and thickness, all three.

The two eyes make up a combined report in this same manner whenever you look at any solid object within reasonably near range. A one-eyed person gets only a partial report, because he cannot see around things in this way. His sense of solidity and distance can come only through experience and judgment. He gradually learns, of course, to infer that a thing is solid and reaches back into space, as he notices the way in which light and shade appear on its surface, or the way in which farther parts look smaller than nearer parts. But the two-eyed man can likewise do all this, so his own capacity for correct seeing must always be immensely greater than that of a person with a single eye.

Now see how this principle of two-eye vision works through a stereograph. Take, for instance, the 85th position in this Norway tour (using Stereograph 684 —"Zigzags of the famous Grjotlid road; mountain milkmaids on the way near Marok"). First cover up one-half the card and look at the other half without the stereoscope, just as you would do with any ordinary photograph made with a tourist's kodak. Of course, you know the zigzag road must be a considerable distance away, because it looks so small, and you know the sod-covered farm buildings must be considerably lower than our own standpoint, because we see so much of their roofs. It seems as if we probably got a pretty accurate idea of the place from the report of a one-eyed camera.

But now just put the stereograph in the stereo-scope rack, and, looking through the lenses, see the same place as if you were standing bodily where the binocular camera stood and using two eyes instead of only one . . . !

Our instinct is to draw back hastily from the dizzy edge of the cliff on which we find ourselves perched ! We can actually see the big empty space between us and that ragged, rocky mountain-side. It seems as if we might easily pick up one of the small stones underfoot and fling it straight out into the airy gulf before us. The difference between seeing with one eye and seeing with two eyes needs no further exposition.

The fact that the girls with the milk pails, small as their photographed images are on the card, should seem to stand out life-size when viewed through the stereoscope, is perhaps surprising until one thinks carefully about what the case involves. Everybody has noticed that the farther away a person is the smaller his form appears. Shut one eye and hold a silver half-dollar six or eight inches away in front of the other eye, while you try to watch a full-grown man walking down the street, fifty feet away, outside your window. You will find the small disk of the half-dollar can hide him completely, i. e., that an object only an inch and a half high, six or eight inches from your eye, fills the same angle of vision as an adult man fifty feet away. Now, since we practically look through the stereograph as if through a window, the effect of its lenses is to translate those inch-and-a-half images of the milk girls on the card a few inches away, into the full-size figures of the real, live girls several feet away, across the road.

Of course, it is not promised that seeing Norway through stereographs can be a complete equivalent for the actual journey. It is through the sense of sight alone that we are to get our experiences of the land and the people. But, as has been remarked by a writer on experimental optics :

"Our sense of location is determined, in nearly all cases, not from what we hear or feel, but from what we see. When we look at ordinary photographs—in our hands, or on a wall—we always see the book or frame or part of the room about us as well as the pictured scene, and consequently we continue to have a distinct sense of our location in the place where the picture is. In using the stereoscope, however, the hood about our eyes shuts our room away from us, shuts out the America or England that may be about us and shuts us in with the city or the people standing out beyond the stereoscopic card."

But the experience of seeing other places just as if we were there can be thoroughly sensible and satisfactory only when we know just where "there" is. The special maps* accompanying this guidebook tell where we are each time we take a new standpoint for observation. Notice that every position in the whole tour is located on one or more of the maps, plainly marked in red with a number corresponding to the number given in parenthesis on the stereograph mount. The apex, or point from which two red lines branch, is the spot where we stand. We look in each case over or through the space included between the branching red lines. Where one of the diverging lines is shorter than the other, that indicates that we shall not see quite so far on that side of our field of vision as we see at the other side. A very little experimental use of the maps will make their idea perfectly clear. Be sure to refer to the proper map, according to instructions, each time, before you begin to look at the place itself ; then you can look with definite, accurate knowledge exactly where you are, what is around you and what lies before you, and the satisfaction and pleasure of the experience will be immensely increased. The very slight trouble involved in consulting the maps will be found repaid many times over by the help it gives in making one feel himself to be "on the spot."

If, then, through the right use of the special maps, we know the exact location of the particular spot where we stand and know exactly the direction in which we look and the distance to which we can see, we may certainly have a distinct sense or experience of being there in person.

That we do actually gain that experience is practically proven by the fact that, ever afterwards, when one of the scenes thus known is called to mind, we go back in memory to the place itself—not at all to the room in America or in England where we had used the maps, stereoscope, and stereographs.

Of course, the "travel experiences" which are made possible by such use of maps, stereoscope and stereo-graphs have limitations as compared with those of an actual journey. One has no sense of muscular exertion in moving about ; the air he breathes is unchanged ; the people he sees do not speak ; the element of color is only suggested—not made visible—in the landscape. The feeling of "being there" may last only a few moments at a time. One's feelings may not, be quite so keen as they would be if he stood bodily' in the distant land. Nevertheless, this sort of "travel experience" is, so far as it goes, absolutely genuine, differing not in kind but only in degree from that of the actual tourist.

James Henry Breasted, Professor of Egyptology and Oriental History in the University of Chicago, says in the preface to his volume on Egypt Through the Stereoscope:

"It was with peculiar satisfaction that I made the acquaintance of your system of `stay-at-home travel' among the people of the East. By its use an acquaintance can be gained, here at home, with the wonders of the Nile Valley, which is quite comparable with that obtained by traveling there. In my judgment, there is no other existent means by which this result can be accomplished. The map system, simple, ingenious and pedagogically sound, first furnishes a clear idea of locality in every case, and with this in mind your superb stereograph furnishes the traveler, while sitting in his own room, a vivid prospect as through an open window, looking out upon scene after scene, from one hundred carefully selected points of view along the Nile. . . . The joys of travel are thus extended to that large class of people who thirst for an acquaintance with the distant lands of other ages, but are prevented by the expense involved or by the responsibilities of home, business or profession. To all such I most heartily commend your tours through foreign lands of the ancient world, and I can confidently assure them in these tours they will find a source of untold pleasure and instruction, immensely widening the horizon of daily life, and more truly making the user a `citizen of the world' than he can ever hope to be without actually visiting these distant lands."

Instructions

1. Experiment with the sliding rack which holds the stereograph until you find the distance which best suits the focus of your own eyes. This distance varies greatly with different people.

2. Have a strong, steady light on the stereograph. Take care that the face of it is not in shadow. It is a good plan to sit with the back toward the window or lamp, letting the light fall over one shoulder directly on the face of the stereo-graph.

3. Hold the stereograph with the hood close against the forehead and temples, shutting off entirely all immediate surroundings. The less you are conscious of things close about you, the more strong will be your feeling of actual presence in the scenes you are studying.

4. Think definitely, while you have your face in the hood, just where your position is, as learned from the maps and explanatory text. Recall your surroundings to mind—i. e., think what is behind you ; what lies off at the right ; at the left. You will find yourself richly repaid for the effort by the fuller "real"-ness of each outlook.