415 
' Scientific Intelligence, — Arts, 
Rouelle, in 1777, published the fact, that sea- water formed spots 
of amalgam upon the walls of a silver vessel in which it had 
been distilled, and that the salt, which was produced, treated 
with sulphuric acid, gave rise to a mercurial deposit in the neck 
of the retort. Fifteen years after, Westrumb, making concen- 
trated sulphuric acid act upon salt of the Pyrmont salt-works, in 
presence of the author, equally obtained a product of sublima- 
tion, in which the presence of mercury as well as that of iron 
were determined. Results of experiment, from which the same 
consequences as the preceding may be deduced, have been since 
announced by Proust and Scherer. The author, lastly, having 
prepared muriatic acid with a mixture of salts obtained from 
various salt-works in Germany, has equally collected a volatile 
matter containing mercury and iron. He calls the attention of 
chemists to these phenomena, and, in accordance with M. Proust, 
recommends that a small plate of gold be fixed to the keel of a 
vessel, and it be examined, at the end of a long voyage, if it be 
not covered with mercury. — Professor Wurzer, 
Reid's Academical Examinations. — The first volume of 
this work has just been published, the second and concluding 
one will appear soon. Mr Reid’s arrangement is good, — the 
chemical details corjrect,— the exposition of general principles and 
views luminous ; and the language suited to the subject. We 
have therefore no hesitation in recommending this interesting 
little work to chemical and medical students. 
ARTS. 
24. Composition of an Inlc similar to China Ink. — Take six 
parts of isinglass, which are to be dissolved in double their 
weight of boiling water ; in like manner, dissolve in two parts of 
water one part of Spanish liquorice ; mix the two liquors warm, 
and gradually incorporate with them, by means of a wooden 
spatula, one part of the best ivory-black. When this mixture 
is properl}^ made, it is heated in a water-bath, that the whole of 
the water may be evaporated. The requisite form is then given 
to the paste which remains. The colour and goodness of this 
ink are equal to those of the true China ink. 
25. Engraving on Zinc. — There has lately been published 
by Leske, the bookseller, at Darmstadt, the first large work of 
