506 ANNUAL RECORD OF SCIENCE AND INDUSTRY. 



well on removal from this. A brownish (over-dyed) shade 

 may be imparted by passing the goods through weak sumac 

 and sulphate of iron. 25 C, 1874, XL, 86. 



SCARLET ON HALF-WOOL GARMENTS. 



Boil ten pounds of thoroughly cleansed goods, for half an 

 hour, with one half of a pound of oxalic acid, one quarter of 

 a pound of tin salt, one pound of turmeric, and one pound of 

 cochineal ; then rinse, place six hours in a bath of one quarter 

 of a pound of tannin, reel off, and finish dyeing in a cold fuch- 

 sine-bath. 24 (7, 1874, x., 73. 



CO3RULIGN0N, FROM WOOD-TAR, FOR PRINTING FABRICS. 



Although no method for the utilization of wood-tar is like- 

 ly to prove of as much practical importance as the discov- 

 eries in coal-tar, on account of the comparatively limited 

 quantity of the former produced, experiments have recently 

 been conducted with this in view. Attention was first di- 

 rected, some years ago, by Reichenbach, to a red crystalline 

 precipitate, obtained by treating beech-wood tar with bi- 

 chromate of potash and tartaric acid, or a solution of sesqui- 

 sulphate of iron, and named by him cedriret, which afforded 

 an indigo-blue solution with concentrated sulphuric acid, and 

 a purple one with creosote. More exact recent investiga- 

 tions by Professor Liebermann have led to the production 

 of several new compounds from wood-tar, one of reddish-blue 

 color being named Ccerulignon, on account of the blue solu- 

 tion it affords with sulphuric acid. Further experiments by 

 C. Fischer led to a very simple process for printing a lively 

 orange on silk or wool, by dissolving this substance in hot 

 alcohol, and precipitating it again with water, then thicken- 

 ing the paste with gum-water of the proper consistency, and 

 printing, drying, and steaming the fabric. In steaming, the 

 slight color of the printed portions disappears, and after 

 washing out the thickening a lively orange may be devel- 

 oped on them by treating the goods in a bath of bichromate 

 of potash or of sesqui- chloride of iron. They may then be 

 washed and finished. Attempts to print with it on cotton 

 have not thus far proved successful. Experiments on a large 

 scale are of course necessary to determine the practical value 

 of the method. 8 C, April 2, 1874, 117. 



