All these salts are mild astringents when applied externally, as they coagulate the albumen of the tissues and of any discharge which may be present.
The urine is nevertheless small in amount and contains albumen and blood owing to the local inflammation produced in the kidney by the passage of the poison through that organ.
Kyan's process, patented in 1832, consists in impregnating the timber with corrosive sublimate which, acting on the albumen in the wood, converts it into an indecomposable substance.
It was found that substances like mineral salts, which crystallize well from solution, passed such membranes with comparative ease, while the jelly-like substances such as albumen passed with extreme slowness if at all.
They are of importance, since the higher homologues are identical in many cases with the ptomaines produced by the putrefactive action of some bacteria on albumen and other related substances.
Applied externally lead salts have practically no action upon the unbroken skin, but applied to sores, ulcers or any exposed mucous membranes they coagulate the albumen in the tissues themselves and contract the small vessels.
ALBUMIN, or Albumen (Lat.
Gallic acid does not coagulate albumen when used externally.
Unlike tannic acid, gallic acid does not precipitate albumen or salts of the alkaloids, or, except when mixed with gum, gelatin.
Their soluble salts combine with albumen and preserve it, strong solutions being extremely irritant or caustic, while weaker ones are astringent simply, or even soothing.