If found too light, return to bath and add more logwood liquor and a few drops more violet, and should you find them altogether too dark for sample, extract your color by passing them through a solution of one teaspoonful of oxalic acid in a gallon of hot water; after which rinse them off by passing them through a gallon of boiling water about twice, when you will find your color reduced four or five shades. The oxalic acid renders the feathers a bright yellow.
Boiling water will draw off the logwood and bring out your shade of drab in as much milder form; then proceed to mix a new drab bath the same as per recipe, only using more caution not to get it too dark; enter feathers, bring to shade, using a drop of violet to brighten up color. Be careful in drying not to use starch that has previously been used on a color where acid was used to develop.
STEEL—page [45]. ARMY BLUE—page [59].
PURPLE—page [60]. MAROON—page [51].
FELT DRAB.
Prepare feathers by washing and rinsing thoroughly, or bleaching if needed; after which mix a bath of luke warm water and starch. Enter feathers and manipulate in bath a few seconds between the hands; after which add a small quantity of copperas, about the size of a pea. Enter feathers and let them remain in about half a minute; take out feathers and add a few drops of logwood liquor; re-enter feathers and let them remain in about half a minute; add to bath about a drop of diluted safranine, and if shade be wanted a little on the yellow, a drop of diluted Bismarck brown can be added. Allow feathers to remain in until they look about three shades darker than sample; then take out and dry as usual. If found either too dark or too light, treat precisely as preceding color (steel). Be careful not to use starch that has been used for an acid color.
SLATE COLOR.
To make this color all light colors can be used and some dark ones; only those, however, that do not contain much yellow, as, for example, blues, reds, etc. After preparing for bath by washing and rinsing, or by extracting color if necessary, mix a bath of logwood, about half the usual strength, and enter feathers. Bath must be at boiling temperature, and let them remain in about one minute; after which take out and rinse. Proceed to mix a bath of one quarter ounce of copperas and one gallon of boiling water; enter feathers and let them remain in bath about half a minute; take out and cool off a small portion of the bath, add starch and pass feathers through, squeeze out and dry.