Arsenic in Wall Papers.

Last evening Prof. H. B. Hill gave a lecture before the Boylston Chemical Club, in which he showed the effects of arsenical papers on the human system. The question is of practical importance to every one of us, and in the present state of public opinion, it is our duty to agitate the subject as much as possible. In every country of Europe except England, the most stringent laws are in force against arsenical products, and in England, determined efforts are being made for proper legislation. In America, however, public opinion needs further education. It is popularly supposed that all green papers are dangerous, and that all others are safe. In consequence, arsenical green papers have become unsaleable, and great care is taken to have them safe. A brilliant red dye has, however, been discovered, which is made from coal tar by the use of arsenic, and this enters into the composition of Pompeian red and various browns, where its use would be least suspected. Arsenic is also used to brighten other colors, and as an antiseptic in the size. Since the arsenic gets into the paper in such various ways, it is impossible to tell anything about a paper by mere inspection. Of two papers apparently alike, one may be very dangerous and the other perfectly harmless. Greens, reds, browns, blues and yellows, all are suspicious, and the only safe way is to test them by a process which was described by the lecturer.