Notes. 
[O&ober, 
yoS 
the “ Die Allg. Polyt. Zeitung ”) either be used at once, or 
metallic salts of a black or dark brown colour may be precipitated 
from it, or the precipitate produced by the addition of acids may 
be used as a pigment. 
According to the “ Moniteur des Produits Chimiques,” ostrich 
feathers are bleached in a bath of io grms. barium peroxide to i 
litre water, heated to 30°. In this they remain for forty-eight 
hours, and are then washed, treated with weak hydrochloric acid, 
and dried. 
According to M. Moyret, 40,000 kilos, of copperas, pyrolignite 
of iron, and other iron mordants are used daily in the Lyon 
district for weighting black silks. For whites and bright shades 
sugar is used, to which the author proposes an addition of a 
decodlion of quassia. Silk dresses thus prepared would serve for 
fly-papers ! Stannic chloride, mysteriously spoken of in the trade 
as X, is employed in addition to sugar. Barium sulphate has also 
been proposed, but it deprives the silk of its lustre. 
The following formula for preparing a mordant from lees of 
wine is taken from a recent number of “ Chemiker Zeitung — 
Fresh green lees, with the addition of two-fifths sodium tartrate, 
are evaporated down to one-sixth the original volume. 15 grms. 
of Cologne glue and 10 grms. tannic acid are added. The mass 
is pressed, rubbed over with alcohol and tannic acid, dried in the 
air, and powdered. For use it is to be further mixed with one- 
fifth per cent sodium tartrate. It is recommended for dying full 
shades in wool and silk, and is said to render the aniline colours 
permanent. In dying woollen cloth a decocflion of Saponaria 
root is added both to the mordant and the dye-bath. 
In a communication on the acftion of vinegar upon alloys of 
lead and tin Herr R. Weber shows that vinegar attacks pure tin 
as well as alloys with lead, the quantity of metal dissolved 
increasing with the proportion of lead present. Alloys of tin and 
lead, to which 4 per cent antimony had been added, were also 
attacked, and lead entered into solution. 
Nickelising without electricity may be effected, says the 
“ Moniteur Industriel,” by introducing into a 5 or 10 per cent 
solution of zinc chloride as much of a salt of nickel as is sufficient 
to give it the ordinary colour of a nickel-bath. The articles to 
be coated, previously well cleaned, are laid in this solution, and 
the process is complete in from half an hour to an hour. Cobalt 
can be deposited in the same manner. 
T. Troost has reported to the Societe d’Encouragement pour 
l’lndustrie Nationale on M. Gaiffe’s Galvanic Deposits of cobalt. 
The metal is deposited from a solution of the double sulphate of 
cobait and ammonia, and is superior to nickel at once in hard- 
ness, tenacity, and in beauty of colour. It is much less oxidisable 
than iron, but is very easily dissolved by acids. 
From a report by M. Aime Girard on M. Kuhlmann’s (junior) 
