The advance of photography : its history and modern applications (1911)

HISTORICAL SURVEY 17 But this result was only possible when the technical part of photography had been brought to perfection, and a material better adapted to artistic work than an unyielding silver plate had been introduced. Experiments of Fox Talbot. — In the same year that Daguerre published his process for the production of images on silver plates, Fox Talbot gave to the world a process for preparing drawings on paper by the help of light. Talbot was an English gentleman of fortune, who, like many Englishmen of leisure and means, employed his time in scientific observations. He plunged paper into a solution of common salt, dried it, and then put it into a solution of silver. In this way he obtained a paper which was much more sensitive to light than that employed by Wedgwood. He employed this paper in copying the leaves of plants. Talbot himself says, " Nothing gives more beautiful copies of leaves, flowers, etc., than this paper, especially under the summer sun ; the light works through the leaves, and copies even the minutest veins/' The pictures copied in this way in the sunlight are naturally not durable, because the paper still contains salts of silver, and is therefore sensitive to light. But Talbot offered the means of fixing the pictures — he plunged them in a hot solution of common salt ; in this way the greater part of the silver salts was removed, and the pictures did not blacken to any considerable extent in the light. The celebrated Sir John Herschel carried out this fixing process even more successfully by plunging the pictures into a solution of hypo-sulphite of soda. This salt, which dissolves the salts of silver, was at that time very expensive, costing six shillings per pound. By this means the production of a durable sun-picture on paper, which Wedgwood had in vain attempted, was rendered possible. This method gave, indeed, only pictures of flat objects which could be easily pressed