ARS well remember the assertion of an ingenious lecturer on chemistry and pharmacy in Edinburgh, who still flatters himself with the hope of being able, at some future period, to demonstrate by experiment, "' that arsenic is the true basis of silver." This semi-metallic concrete is very usefully employed in various branches of the arts and manufac- tures ; it is frequently added as an ingredient, to facilitate the fusion of glass, and to produce a certain degree of opacity. Painters use two arsenical preparations, namely, the orpiment and realgar. A very beautiful green pigment may be precipitated from blue vitriol, by a watery solution of white arsenic and vegetable alkali : this, when prepared either with water or oil, affords a permanent colour. It is highly probable that, if arsenic were added to the paint used for wood, it might form an ingredient which would not be liable to be preyed upon by worms. But the practice of painting the toys of children with arsenical pigments, deserves severe censure ; as they are accustomed to put every thing into their mouth. In dyeing, it is likewise of great service. Combined with sulphur, it has the property of readily dis- solving indigo ; for which purpose it is used in the printing of calico, and other cloth. On exposure to the air, however, the arsenic is precipitated from this solution, and may be farther employed in pencil colours. Some dyers are said to understand the art of imparting beautiful shades of colours to furs, by arsenical solutions. ARS [107 In rural and domestic economy, this concrete is also frequently re- sorted to with great advantage, though not always with due pre- caution. Farmers dissolve it in lime-water, for steeping wheat, in order to prevent the smut ; and it is li ^ewise asserted, that the husband- men of Flanders and Germany use it for fertilizing the earth,by sprink- ling the soil with a solution of arsenic in dung- water. In medicine, it has long been known as the basis of the most celebrated cancer-poivders, espe- cially those of Pluxicet, Dr. Hugh TvIvrtin, and probably also, of Guy's. A weak solution of it in water, is directed by Dr. Way, of Wilmington, for effectually cleans- ing foul ulcers, and removing im- purities of the skin : it is prepared by boiling one ounce of white arse- nic in two quarts of water to three pints, and applying it once or twice a day. When it is used for extract- ing, or discussing, cancerous or schirrous tumors, that are not ul- cerated, the above-mentioned Dr. Martin, a late physician in Ame- rica, previously ordered a blister of Spanish flics to be applied to the part, with a view to open the pores of the skin. But, as he prescribed it empirically, and indiscriminately in all cancerous cases, we were not surprized to learn from his old professor, Dr. Benj. Rush, one of the most candid and enlightened American practitioners, that his pupil has often been unsuccessful in the application of his arsenicated powder*. In the cure, of agues, a solution of this mineral has been strongly recommen.ied, and administered with
- It is presumed, that rtie liquid medicines, nnw secretly exhibited by a physician in the
metropolis, who positively maintains that hi cure* ancirs " by absorption," likewise con- sist
