PhotoHistory

From: PHOTOGRAPHY OF TO-DAY

By H. CHAPMAN JONES, 1913

The Development of Photography (part 1 of 3)

In order to appreciate properly the position that photography occupies at the present day, it is necessary to have a general idea of the steps by which it has come to be what it is. We sometimes have such questions put to us as Who invented photography? Who discovered photography? Who was the first photographer? The endeavor to answer these questions has led to waste of words and sometimes to loss of temper, for those engaged in the discussion have failed to settle among themselves what photography is. Is photography to date from the first attempt to produce a design by light action, the first attempt to get a permanent record, the first successful attempt, or the working out of the first method that “caught on” with the general public? Until such questions are answered we cannot say who was first. It is a matter of definition.

But if we look at the question broadly, we find that photography or light-writing is older than man himself. Before the earth was fit for him to live on the light was at work, and we can still read some of its ancient records in fossilized vegetable remains. In the oldest of historic literature there are references to colored textile fabrics, and it is impossible to imagine that the action of light upon such materials was unobserved. It is not known how old is the practice of exposing linen on meadow land to the free action of air, moisture, and light for the purpose of bleaching it. Those employed in this work can hardly have failed to notice that a shaded portion was changed to a much less extent than a part exposed to the full light, and this difference would constitute a light record of the fact that a part was shaded, and such a record would naturally be accepted as a guide for the treatment or care of the material. It may be objected that if this is called photography then a mere blot of ink must be called a writing. We will not argue as to whether intelligibility is a necessary attribute of all writings, nor refer to human intervention, nor consider the connection of motive with the matter, but endeavor to give a concise account of those circumstances that are immediately connected with our subject.

Camera Obscura

We have already seen, and shall see more in detail subsequently, that the camera is not of fundamental importance in photography. But as it has been and even still is often considered to include the lens, the camera and lens being regarded together as the image-producing instrument, the history of the camera is not without interest. In countries where the sunshine is much more brilliant than we in England are accustomed to, and where its very brilliancy leads to the necessity of excluding it, there must often have been noticed an image of exterior objects on the wall of a room opposite a keyhole or chink. Major-General Waterhouse states that in India he often saw vivid pictures so produced on the wall of his bungalow. This is the very essence of the camera. We only want a bigger hole to let in more light and a lens or mirror to get a sharp image and the apparatus is complete.

Roger Bacon (born 1214, died 1284) was, so far as known, the first to refer specifically to such an apparatus, though the use of image-producing lenses and mirrors was known more than a hundred years before he was born. Bacon refers only to the use of a mirror or speculum for producing the picture. The first reference to the use of a lens for this purpose appears to have been made in 1568 by Danielle Barbaro in a book on perspective published in Venice, who directs that “an old man’s glass convex on both sides, not concave, like the glasses of youths with short sight,” should be fixed in a hole in the window, and all light stopped out except what comes in through the lens. A piece of paper is held at the most suitable distance from the lens, and the image, he says, will be better if the lens is partially covered so that only the central portion is used. Giovanni Baptista della Porta, who lived in the sixteenth century, has often been stated to have invented the camera, but he appears only to have popularized it and given rather more particular instructions concerning it, doubtless introducing a few minor improvements in its details. The aim of these and numerous other of the earlier users of cameras, was either the amusement of spectators, or to illustrate the rules of perspective, or else to facilitate the drawing of the object depicted. There could have been no thought of the application of the apparatus to photography, because there was not available any suitable sensitive material to receive the image on. To them the very idea of it, if it had been suggested, would have appeared as wild and impossible as the use of steam instead of horses for the purposes of locomotion, or the use of the same steam power instead of candles and lamps for the illumination of their dwellings.

Silver Salts

At about the same time that Porta and Barbaro lived the alchemists were still at work, seeking in their enigmatic methods to find a way of turning base metals into gold and to find a method of curing all human ills. Silver chloride, called horn silver, was known to them as a mineral, and there is some evidence that they were aware that it became darkened or blackened when exposed to the light. It is difficult to believe that this was not known long before, as Geber, an Arabian who lived in the eighth century, prepared nitric acid, dissolved silver in it and obtained silver nitrate in crystals. He added sal ammoniac (ammonium chloride) to the nitric acid and so obtained aqua regia, with which he dissolved gold and other substances, and he says that he dissolved silver also in it. When aqua regia acts on silver, silver chloride is produced. Or if, as is very likely, he added sal ammoniac to the solution of the silver in nitric acid, silver chloride would have been precipitated as a white insoluble powder. It would be improbable that experiments of this kind should have been made in daylight without noticing that the silver salt darkened in the light. But there was no reason why special notice should have been taken and recorded of this fact, any more than, for example, that silver was a white metal and copper red.

In 1727 a German physician, Dr. John Hermann Schulze, of many and various attainments, for he was in turn professor of anatomy, Greek, Arabic, eloquence and antiquities, and a historian of ancient medicine, while reading about a certain phosphorescent substance, took it into his head to try to make some. The first operation in its preparation consisted in adding nitric acid to chalk. He took some acid that he happened to have handy, probably it had been used before as it had a little silver in it, and his chalk in a dish to an open window where the sun was shining and began to pour the acid on the chalk. He was soon surprised to see that the surface of the mass changed from white to a dark violet-red where the sun shone on it, but not where the edge of the dish shaded it. He proceeded to investigate the cause of this change, using the pasty mixture in medicine bottles for the sake of convenience, and found that heat would not produce the color. Then he cut out words or even entire sentences in paper, like stencil plates, attached these perforated papers to the bottles of mixture with wax, and exposed them to light. The words were then clearly visible on the contents of the bottles, to the wonderment of curious onlookers. By shaking the bottle, the darkened portions, which were only on the very surface of the sloppy or pasty mass, became mixed up with the bulk and the experiment could be repeated. He investigated the matter and found that it was the silver that caused the sensitiveness to light, and that the chalk might be replaced by magnesia, white lead, and other similar substances. He not only did not attempt to fix the photographs that he produced, but was particularly careful to keep the mixture in such a condition that it could easily be shaken up to get rid of the impression and so be ready for the next experiment.

We see in these experiments of Schulze the true spirit of careful observation and experimental inquiry, for during the previous hundred years or so the aims and mysticism of alchemy had gradually given place to what we now understand as scientific methods. It is easy to say that whatever Schulze did that had not already been done was not worth the doing, for the sensitiveness of silver salts to light had been known long before. But every little step helps the cause forward, and the emphatic demonstration of a known fact may be even more helpful than the discovery of a new fact or a new application.