Chromo-lithography (printing in colors from stone) was experimented on by the great inventor. He outlined its possibilities by saying, that he verily believed that printed pictures like paintings would sometimes be made thereby, and whoever has seen the productions of our Boston firm, L. Prang & Co., will bear him out in the verity of his prediction. When Prang touched this art in 1856 it was in its infancy in this country. Stray specimens of more or less merit had been produced, especially by Martin Thurwanger (pen work) and Fabronius (crayon work), but much was left to be perfected. A little bunch of roses to embellish a ladies' magazine just starting in Boston, was the first work with which the firm occupied its single press. Crude enough it was, but diligence and energy soon developed therefrom the works which have astonished not only this country but even Europe, and the firm, which took thereby the lead in their speciality of art reproduction in color, has succeeded in keeping it ever since from year to year without one faltering step, until there is no single competitor in the civilized world to dispute its mastery. This is something to be proud of, not only for the firm in question, but even for the country at large, and to crown its achievements, the firm of L. Prang & Co. have this year made, apart from their usual wonderful variety of original Christmas cards and other holiday art prints, a reproduction of a flower piece of the celebrated Belgian flower painter, Jean Robie, and printed it on satin by a process invented and patented by Mr. Prang. For truthfulness as a copy this print challenges the admiration of our best artists and connoisseurs. The gorgeous work as it lies before our eyes seems to us to be as perfect as if it left the very brush of the master, and even in close comparison with the original it does not lose an iota of its charms. Of the marvellous excellence of this, the latest achievement of this remarkable house, thousands who visited the late exhibition of the Massachusetts Charitable Mechanic's Association and saw Messrs. L. Prang & Co.'s, extensive exhibit, can bear witness. Everybody who looked at the two pictures, the original masterpiece by Robie and its reproduction by Prang, side by side, was puzzled to distinguish which was which, many pointing to the reproduction as the better, and in their eyes, therefore as the original picture. The same was true with regard to many more of this justly celebrated firm's reproductions, which they did not hesitate to exhibit, alongside of the original paintings. Altogether, their exhibit with its large collection of elegant satin prints, its studies for artists, its historical feature, showing the enormous development of the firm's work since 1856, its interesting illustration by successive printings of how their pictures are made, and its instructive and artistic arrangement of their collection, made it one of the most attractive features of the fair.