| A very good black is the prussiate or steam aniline black whose cheapness should recommend it. |
| To a solution of sulphate of iron add a drop or two of a solution of prussiate of potash, and a blue colour will be produced. |
| The goods, previously polished and finished, are heated to a bright-red, and rubbed or sprinkled over with prussiate of potash. |
| As soon as the prussiate appears to be decomposed and dissipated the articles are plunged into cold water. |
| The piece being heated may then, if small, be dipped in the prussiate of potash, or if large have the same spread upon it. |
| A mordant of blue vitriol is commonly first given, followed by a bath of prussiate of potash. |
