JKfecellmig 
Chinese Vermillion. — The Nouveau Journal Asiatique contains a transla- 
tion by M. Stanislas Julien from a Chinese encyclopedia, giving a full 
account of the preparation of vermillion. After stating, that the best is 
found native in Mayang, and is used for painting the houses of princes 
and persons of distinction, it goes on to give the process for making it 
from crude mercury. A crucible of porcelain, or a double vessel of metal 
is employed indifferently for this purpose ; to one pound of mercury, two 
pounds of sulphur are added ; the mixture is triturated until it forms a 
blackish powder ; it is then put into a crucible, which is covered with an 
iron plate held down by a transverse iron bar firmly attached to the ves- 
sel. All the openings are carefully luted and the pot placed upon an iron 
tripod, under which a fire of resinous faggots is maintained for a consider- 
able time ; whilst the cover is kept cool by means of an old swab soaked 
in water. The mercury combines with the sulphur and sublimes in a 
fine powder. The vermillion on the inside of the cover is the brightest. 
One pound of mercury gives fourteen ounces of vermillion of the first 
quality, and three and a half of the second. When intended to be used 
in writing, it is ground with gum water, and made into small cakes. 
Rubbed upon a stone pallet it presents a red of the greatest brilliancy; if 
pounded on a tin slab, it forms a black colour, and is then fit for the var- 
nishers and gives to objects a glistening tint which enhances their price. 
Mixed with the oil of the Thoung tree it is very brilliant, but the addition 
of the varnish destroys this and gives it a dark black colour. 
Journ. Asiatic Soc. Bengal. 
To separate magnesia from potassa and soda. — M. J. Liebig proposes the 
following plan for this purpose as more simple than any hitherto de- 
scribed. It is specially designed to recognise the presence of sulphate 
of soda in sulphate of magnesia. With this view, the sulphate of mag- 
nesia is precipitated by the sulphuret of barium, which separates all 
the magnesia from the soda; this latter remains in the fluid in the state 
of sulphuret of sodium, mixed with an excess of sulphuret of barium, by 
neutralizing with sulphuric acid, evaporating and heating to redness, the 
Vol. I — No. 2 22 
