Show Dyes From Lichen The use of lichens as sources of dye dyo V s of long standing The famous blue and purple dyes of the East so frequently frequently fre- fre mentioned In history were In V 5 all probability extracted from the Rocella Roccella Roc Roc- ella celIa lichen which r times recent cent times Umes been extensively ly used In France for the g gorgeous rg us coloration n of silks Lichen d dyes e are secured by pulverizing the P plant ant body termed the and applying appl ap- ap pl plying alkali alkan to extract t the coloring matter r. r One lI lichen hen dye litmus finds wide wide application catlon In the science of j chemistry |