Chemistry and Chemical Arts. 131 
6. Transformation of vegetable substances into anew principle, 
by Bracconor. (Ann. de Ch., t. 52, p. 290.)—Vegetable sub- 
stances produce when heated with concentrated nitric acid, com- 
pounds very different from those afforded when dilute nitric acid is 
used. Saw-dust, cotton, linen, fecula from the potatoe gum, issoline 
and saponine, heated with concentrated nitric acid, are transformed 
into a peculiar mucilaginous substance, called by Bracconot, Xiloi- 
dine. It is transparent, and is reddened by turnsole; cold water co- 
agulates it, and boiling water softens, without dissolving, it. It is in- 
soluble in alcohol and ammonia; and caustic potash dissolves it with 
great difficulty. On the other hand, the acids dissolve it in great 
quantity without altering it; the solutions leave upon bodies a bril- 
liant varnish, perfectly insoluble in boiling water. It inflames by 
heat with great facility.—Jdem. 
7. Creosote, by Lizsic. (Ann. de Chim., t. 53, p. 825.)—Dr. 
Reicuensacu has enriched the history of the dry distillation of or- 
ganic substances with the discovery of this new body, which, on ac- 
count of the great number of its properties, and of its being the ba- 
sis of smoke, and pyroligneous acid, possesses the deepest interest 
for chemists, and will undoubtedly become extremely important in 
domestic economy. Its medicinal properties will likewise lead to its 
use in medicine. 
Its preparation presents at present considerable difficulty, although 
it will undoubtedly be simplified, when its properties become better 
known. Thus far it has been obtained from oil, from pyroligneous 
acid, and from tar. ‘The processes are slightly different, according 
to the substances employed. - We give only that for pyroligneous 
acid. 
Dissolve in impure pyroligneous acid at 70° or 80°C, as much 
sulphate of soda as it will take up: after a little while, separate the 
oil which makes its appearance upon the surface of the fluid, leave 
it to repose for some days, in order to separate a new portion of py- 
roligneous acid, and of sulphate of soda, and afterwards saturate it 
while hot, with carbonate of potassa, until the effervescence is over ; 
a thick oil is separated, which is distilled with water; an oil of a 
pale yellow color is obtained, which is agitated repeatedly, with fresh 
portions of diluted phosphoric acid; the liquid is allowed to rest, 
and then washed with water until it manifests no farther acid reac- 
tion: finally it is distilled in a retort, with a fresh quantity of water 
