Hi, Rowena,
The Roman naturalist and historian Pliny recorded that the slag by-product of silver refining was found to give special healing qualities to medical plasters, particularly those applied to open wounds. Oxides of silver were likely the main constituent of such slag. A 20th century follow-up to Pliny's observation was undertaken in-vivo by J.H.Muller in 1936 and reported in Hill & Pillsbury in 1939 (p. 4): "...An oily dispersion of anhydrous silver oxide containing 5 per cent silver oxide will yield its entire silver oxide content to the (animal) system by simple inunction on the surface of the skin or by application to open lesions or mucous surfaces and that, when so absorbed, silver in some form or another can be readily found in both urine and feces of the treated animal. The analysis of the skin and underlying tissues treated by inunction failed to show any sign of deposits of silver or any compounds of this metal so that complete systemic distribution of the administered oxide is more probable." According to Hill & Pillsbury, Muller felt his results pointed to a "probable completeness of elimination from the animal system, of silver oxide." Also, Muller did an in-vivo experiment on himself. He rubbed silver oxide ointment (Novoxil) on the back of his hands daily for many months but could demonstrate no staining effect on or about the area treated. Similar treatment with a dispersion of silver acetate resulted in marked staining. Presumably, silver nitrate would have stained likewise. Please keep us informed of the outcome of your intriguing experiment, Rowena. Best regards, Matthew
