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Scientific Intelligence.— Arts. 
much better to have hammered them upon their angles, which 
would have had a much greater condensing effect .— Technical 
Repository , December. 
32. Blue and Green Colours derived from Althaea rosea . — 
M. Bauhart, apothecary at Weimar, has discovered an easy pro- 
cess for obtaining a beautiful blue from the leaves of Althaea 
rosea of Willdenow. The flower furnishes a very beautiful 
green, which may be used for dyeing wool, wood, horn, he. 
The blue colour obtained from the leaves is averred not to be 
inferior to indigo. Nothing is said of the modes used by the 
discoverer for extracting the colours. 
33. Melaina . — Signior Bizio considers the black matter of 
the ink of the cuttlefish, as a substance sui generis , which he 
calls Melaina , from (Axas and ui). It is obtained by digesting 
the ink with very dilute nitric acid, until it become yellowish, 
washing it well, and separating it by the filter ; it is then to be 
frequently boiled in water, one of the washings to be a little al- 
kalized, and, finally, with distilled water. The Melaina is a 
tasteless, black powder, insoluble in alcohol, ether, and water, 
while cold, but soluble in hot water ; the solution is black. 
Caustic alkalies form with it a solution even in the cold, from 
which the mineral acids precipitate it unchanged. It contains 
much azote. It dissolves in and decomposes sulphuric acid. 
It easily kindles at the flame of a candle. It has been found 
to succeed as a pigment, in some respects better than china ink. 
— Dub. Phil. Journ., Nov. 1825. 
34. New method of preparing Quills . — The following is the 
manner in which M. Schloz of Vienna proceeds in the prepa- 
ration of quills for writing, by means of which he renders them 
more durable, and even superior to the best Hamburgh quills. 
For this purpose he makes use of a kettle, into which he pours 
common water, so as to occupy the fourth part of its capacity ; 
he then suspends a certain quantity of feathers perpendicularly, 
the barrel lowermost, and so placed, as that its extremity only 
may touch the surface of the water ; he then covers the kettle 
with a lid properly adjusted, boils the water, and keeps the fea- 
thers four hours in this vapour bath. By means of this pro- 
cess he frees them of their fatty parts, and renders them soft 
and transparent. On the following day, after having scraped 
