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Rosaniline, or Fuchsine

The duced, the mixture commences to boil and alprincipal methods for the manufacture of fuch- dehyde begins to distill over, the remainder of sine employ arsenic acid, the reaction being the said mixture being added through the brought about in a cast iron still with mova- tubulus as required. No further purification ble head, connected with a condenser, and is needed. provided with a manhole, and also a place for a thermometer. This still sits in a jacket containing a hot bath of palm-oil, which keeps it at a temperature of from 320° to 356° Fahr. A charge consists of 100 parts aniline and 200 parts arsenic acid, and the reaction is ordinarily completed in about 6 hours, sometimes in 5, but at others only in 12 hours, during which time the temperature is carefully regulated.

Assays are taken from time to time, and the 2558. Το Make Aniline Colors Soluble in Water. The aniline colors insoluble in water may, according to Dr. Zinsman, be rendered soluble in the following way:-A solution of gelatine in acetic acid of about the consistence of syrup is first made, and the aniline color in fine powder is gradually added, stirring all the time so as to obtain a homogeneous paste. The mixture is then to be heated over a water-bath to the temperature of completion of the process is known by the boiling water, and kept at that heat for some pure bronze color of the sample. The fused time. Colors in this state, if a very clear gelmass is transferred to a tank, in which, after atine is employed, will be applicable to many cooling, it is broken up, and at once treated decorative purposes. Bookbinders, paperstainers, and printers will find them useful. They may also, it is said, be used to color confectionery and soaps. Before they are used for confectionery, however, it will be well to make sure that no arsenic is present. with water and steam. The base fuchsine (rosaniline) dissolves, leaving behind the resinous products of the reaction; the arsenic acid s separated by the addition of milk of lime.

The filtered solution, after properconcentration, eposits, on cooling, fine crystals of fuchsine, 2559. Injurious Effects of Impure Is do also the first mother liquors. An infe- Alcohol upon Aniline Colors. Dr. Tillior quality of fuchsine is obtained by adding a manns has examined several varieties of alortion of salt, varying in quantity. cohol, and tested the effects upon aniline