DISEASE FROM VAPOR OF NITRIC ACED.
The vapor of nitric acid is a source of injury in some occupa tions. It is experienced, mostly, by those who are engaged in the process of fur-dyeing. The acid is used in this process for two purposes, for freeing the substance of the fur of greasy matter, and for giving a dark yellow or brown stain. The vapor of the acid rises very freely, and is, of necessity, inhaled by the work men. The symptoms produced are dryness and redness of the throat, constant constipation, and severe pain at the back of the head, with sensation of weight and often with a sense of giddiness.
Now and then in the practice of the chemical laboratory the inhalation of the vapor of nitric acid produces very serious effects. A man who was engaged in my own laboratory once suffered se verely from this cause, the symptoms of difficult breathing and cough lasting for several days. In March, 1s63, Mr. Steward, a master in the school of the Edinburgh Royal Institution, together with one of the janitors of the school, died from this cause. A bottle of nitric acid was accidentally spilled and the two men in haled the vapor. Neither of them at the time felt pain; but both died, one in about ten, the other in about thirty hours after the occurrence of the accident.