Show FAST COLORS troll for alo rr DC of many color in order to determine the fastness ol 01 colors with which fabrics have dyed alio following tests may be macci eb boil a small strip of lie lissul to be in soap water and in limewater lime water tho color should change very little if however it in cither case turns yellow or brown tho color is not fast yellows boil strips of tho tissue in water in alcohol anil in limewater lime water it sn tho two last boiling solutions tho tissue takes a yellow color and the liquid a reddish color the dyo is not fast blues vast blue alion boiled in alco hoi should not aal acl alic color of the bath and the color itself should not change to red or reddish brown in a warm solution of acid and water or alcohol and tho bath takes a reddish color alio bine is not fast violtte when violet colors boiled in mixture of equal parts of water and alcohol give up their color or change to or brown when boiled in dilute acid giving a reddish color to the bath they can not bo colored fast of violet shades only madder violet and tho combination of indigo and cochineal can bo considered fast gracin whan boiled in d llulu alcohol fast colors should not color tho bath green yellow or blue in dilute acid tho bath should not become cither blue or red brount browns which when in water color the bath red or when left for a time in alcohol color alio bath yellow arc not fast colors blacks if a dilute acid 0 o lution is colored red on dipping in it i strip of black tho color of which changes to reddish brown or to brown the color is not fast logwood if thi color of tho changes to blue alio black has a ground of indigo and ltd degree of fastness on alio deepness of the indigo bottom black may bo considered perfectly fast being boiled with dilute abid tho liquid is colored yellow to discover whether a black has a bottom of indigo boil a strip in a rodn bath if indigo is present the t buu retains its black color or to bauo or green but it alus black is dupure tannin black it will acconio brown journal of fabric |