We need not here enter into the details of the wet-plate process, which is still very frequently adopted for photomechanical work, and is described in a later chapter of this book. For the ordinary photographer it was attended with many very serious drawbacks. The pouring of the iodised collodion on to the glass plate in such a way as to form an even, homogeneous surface was a very delicate operation, involving no little deftness and skill. The silver bath was an expensive item, requiring to be constantly watched, and liable to get out of order in all sorts of unaccountable ways. All the preparations had to be gone through within a few minutes of exposure. So that the photographer of landscapes was compelled to burden himself with a huge parcel of paraphernalia, including a portable dark room or developing tent, bottles of solutions, and dishes. Not more than one or two exposures were possible during a day's excursion. The time of exposure, though less than with Daguerrotypes, was still very far from short, and required of the sitter for a portrait an enormous amount of patience and self-control. Then, again, the whole business was very messy and embarrassing, especially for the amateur. He was a "marked man," with indelible stains on face and hands. Dribblings of silver nitrate leaked out of his dark slide on to clothes, carpets, and furniture, to the distress of all good housewives.

But they were giants in those days. The wet-plate period is generally regarded as the Golden Age of photography. Nearly all the valuable subsidiary processes had their origin during its sway. The amount of good work done was enormous. Perhaps because of the many difficulties and the conscientiousness and care essential at every stage, it enlisted in its service a strenuous, resourceful race of operators, and undoubtedly much of their work, particularly that of the late Francis Bedford, Vernon Heath, H. P. Robinson, and W. England (the two last of whom have, of course, lived to illustrate the newer methods) will compare for brilliancy and fine detail with any produced at the present day. The wet plate died hard. Years after the ready-made dry plate had become an ordinary article of commerce leading professional firms were still adhering to the older rival.

Dr. R. L. Maddox, of Southampton, is generally regarded as the inventor of the dry plate. An account of his experiments in this direction appeared in the British Journal of Photography in 1871. With its introduction the names of I. Burgess, R. Kennett, and C. Bennett must also be associated. Some old experts still contend that its advent marks the commencement of an age of degeneration. Certainly the last two decades of the nineteenth century witnessed a vast revolution to the profit of all interested commercially in the manufacture and supply of things photographic. From an academic pursuit for the few, and a difficult and expensive trade, photography was suddenly transformed into a pursuit for the million, commending itself readily to the man whose purse is slender and hours of leisure few in number. The gelatine film, whether on glass or celluloid, is ready for instant use, and a supply can be carried in apparatus of small compass and light weight. After exposure it may be packed away for development whenever convenient, even at the end of a lengthy tour. The subsequent processes have all been simplified, and involve no specialist's knowledge of chemistry or any other science beyond common sense. Fresh supplies are obtainable in the smallest country town; dark rooms are to be found almost in every street. So much has been done by the manufacturer to make the path plain towards success that, with a little artistic instinct, the merest tyro will sometimes attain a result that the professional might envy.

Even more significant is the manner in which photography, since the invention of the dry film, has extended its operations for the advancement of science, and for the delight and instruction of every class of the community. The most ordinary photograph is a record of something, stimulating the faculty of observation, memorising for future use more than can be perceived at a casual glance. Architect and engineer obtain by its aid more accurate and useful ideas of buildings and machinery than could be conveyed by any but the most laboriously prepared drawings. A weekly report of work in progress may be comprised in one or two snapshots. Scarcely less useful is the camera in the hands of the detective, or the medical specialist. Its revelations of wild nature in its living haunts are the delight of the naturalist; the astronomer finds it indispensable; and in connection with the X-rays the dry plate has even introduced the scientific investigator to a knowledge of the unseen.

Thanks to the dry plate we find in our daily newspapers faithful pictures of events that took place only a few hours before. We can step into a cinematograph theatre and see these happenings in their actual details and surroundings, with all the living movements, just as if we were present at the time and place of their occurrence. It is safe to prophesy that, in the course of a few years, satisfactory photographs in the veritable colours of nature will be an everyday matter; without the dry plate not one of the many steps already reached in this direction could have been attempted.

Most of the creators of modern photography are still with us, and it is invidious to particularise. The roll of honour would have to be a very long one, and in the attempt to compile it, some would certainly be forgotten who ought to be found inscribed upon it. We only dare mention here the veteran Sir W. de W. Abney, whose investigations in almost every branch are invaluable, and who may specially be termed the father of the many processes involving the bichromates; Dr. J. M. Eder, the famous chemist and inventor of many new developers; Mr. W. Willis, who with Captain Pizzighelli perfected the platinotype process; and Sir J. W. Swan, who rendered the carbon process popular. So fascinating a study was certain to attract the attention of the greatest minds; each has been content to add his own contribution to the general fund of knowledge, often without seeking for any recognition or reward beyond the pleasure incidental to the pursuit itself.