M. TECHNOLOGY. 527 



ties removed from, the garments. He suggests, therefore, 

 treatment of the impure liquid first with dilute soda solu- 

 tion, and then distillation with steam in a peculiarly con- 

 structed apparatus, which he describes, which acts continu- 

 ously, and with which from 2000 to 2500 quarts can be puri- 

 fied in twelve hours, dependent on the boiling point of the 

 hydrocarbon. The distillate is desiccated. 14 (7, CCXIIL, 

 1874,399. 



VIOLACEIN, A NEW BLUE DYE-STUFF. 



The following process has been patented by Gottheil, in 

 England, for the preparation of a dye-stuff, which is said to 

 afford a permanent dark-blue color with a slight copper-red 

 lustre. Products resulting from the distillation of tar are 

 stirred with enough of caustic potash to impart a slight 

 alkaline reaction, and the mixture is then washed with wa- 

 ter, and again distilled. The oils passing over at about 347 

 are then washed with a weak lye, to remove carbolic acid 

 and creosote, and are afterward mixed w T ith a strong solu- 

 tion of caustic potash, and oxidized by any of the usual 

 methods. The dye-stuff thus produced is separated by fil- 

 tration, washed, and dissolved in an acid. Caustic potash 

 is then added to the filtered solution, and the precipitate 

 formed is washed in alcohol, and finally dried. It is entirely 

 insoluble in alkalies, alcohol, or soap solution, but forms a 

 red solution with dilute acids. 6 (7, March 25, 1875, 118. 



STAMPING-INK, FOR COTTON AND LINEN, UNAFFECTED BY 



CHLORINE. 



An ink suitable for marking cotton and linen goods, that 

 are to be bleached, may be prepared by diluting one part of 

 coal-tar with one of benzine, and stirring in one tenth of a 

 part of lampblack, until a homogeneous mass is formed. It 

 should be dried after stamping, and may be rendered thin- 

 ner or thicker by varying the quantity of benzine. 24 (7, 

 XVI, 1875, 124." 



DYEING HORSE-HAIR. 



Horse -hair may be dyed as follows: Brown: The hair 

 must first be thoroughly cleansed by placing it in a soap 

 bath, heated to 133, for twenty-four hours, and moving it 



