Show perfecting fireproof paper documents Doca ments written on paper made from ni a besto fiber with alth inks prepared from the nitrates nitra tea of iron and cobalt hava have withstood a red heat for two hours without wag damaged in acv ay so carrage resulted until the intensity of the heit heat 11 as increased considerably elder sider ably and the document was as exposed po ed in it for ten houra hours it IS 1 expected that further and study will result in the perfection perfect loa of a and ink practically indestructible tible by fire |