Page:Popular Science Monthly Volume 6.djvu/687

Rh While the encouragement of art—pure and simple—thus formed the main object of the Society, investigation was directed toward many practical subjects related to the central idea. Endeavors were made to improve the materials employed by artists, and much attention was devoted to the various engraving processes as they gradually came into vogue. Wood-engraving, aquatint, and mezzotint, were the subject of anxious care, as were improvements in pigments, oils, and varnishes.

Bronze casting and chasing, iron-castings, and artistic metal-work, were also encouraged, and at a later date, when Alois Senefelder, an actor of Munich, discovered lithography, the new art was first introduced to this country under the auspices of the Society of Arts. Steel engraving was also first taken seriously in hand by Mr. Charles Warren, chairman of the Fine Arts Committee, who, at the suggestion of Mr. Gill, chairman of the Mechanics Committee, adopted a new method of treating steel plates. Previously to this, many attempts had been made to engrave on steel. Albert Dürer is said to have etched on steel, and there are four plates etched by this artist, impressions of which exist in the British Museum, and which in all books of art are recorded as having been executed on steel. In the attempts to revive this art, pieces of saw-blades were selected as the most promising material, but these efforts were attended with very little success. A Mr. Raimbach then endeavored to engrave on blocks of steel, but without achieving any material advance. Mr. Gill now drew the attention of Mr. Warren to the method employed at Birmingham in the manufacture of ornamental snuffers and other articles of cast-steel. The process employed at Birmingham was "to subject the steel, after having been rolled into sheets, to the process of decarbonization, by means of which it was converted to a very pure soft iron, being then made into the required instrument or other article. The ornamental work is engraved or impressed on the soft metallic surface, which, by cementation with proper materials, is again converted superficially into steel. Mr. Warren modified this process, and obtained thin plates of steel capable of being acted upon by acids and cut with the graver, without destroying the cutting edge of the tool—as was the case with the saw-blades. The resulting plate yielded a greatly-increased number of impressions." When brought to perfection, steel plates were found equal to the production of ten or twelve times the number of impressions yielded by copper plates. Capital was invested in the production of works of a high class, with the effect of spreading far and wide through the country myriads of prints calculated to elevate and improve the taste of the people. This process of conversion and reconversion of steel was soon afterward applied by Perkins to the production of steel rollers. These were first softened and then pressed into the engraved surface of a hardened steel block, and having acquired a design in relief were themselves hardened in their turn, and