By means of a dye process known as the "Primuline Process," very pretty images in various colored dyes can be made upon silks, satins, cotton goods, etc. The material is first dyed in a hot solution of primuline, made by adding about 15 to 30 grains of the dye to a gallon of hot water; a little common salt should also be added. On immersing the fabric, and stirring it about in the solution, it becomes of a primrose yellow color, when it is removed and washed under a cold-water tap. The next process is to diazotize it by immersion for half a minute or so in a cold solution of sodium nitrate, one-quarter per cent., which has been sharply acidified with hydrochloric or other acid. The material is again washed in cold water, but it must be kept in a weak light. It can be hung up to dry, in the dark, or exposed while wet beneath the object of which it is required to produce a positive reproduction. This process gives a positive from a positive, so that any ordinary picture on a sufficiently translucent material—flowers, ferns, etc.—can be reproduced. Printing requires about half a minute in the direct sunlight to half an hour or more in dull weather, or if the material to be printed through is not very transparent. The high lights become of a pale yellow, so that a faint image is perceptible; but this is made visible in almost any color by development in a weak solution (about one-fourth per cent.) of a suitable phenol or amine. The following have been found suitable:

For Red.—An alkaline solution of -napthol.

For Maroon.—An alkaline solution of -napthol-disulphonic acid.

For Yellow.—An alkaline solution of phenol.

For Orange.—An alkaline solution of resorcin.

Brown.—A slightly alkaline solution of pyrogallol, or a solution of phenylene-diamine-hydrochloride.

For Purple.—A solution of a-napthylamine hydrochloride.

For Blue.—A slightly acid solution of amido--napthol-sulphonate of sodium, now better known as "eikonogen."

If the design is to be made in several colors, this can be done by painting on the different developers, suitably thickened with starch. After developing, the material is well washed and dried. With the purple and blue developers it is necessary to wash the material finally in a weak solution of tartaric acid. Wool and silk require a longer exposure to light than other fabrics, and cannot be successfully developed with the maroon or blue developer.