330 
Notes. 
[April, 
Artificial benzoic acid is at present manufactured in large 
quantities from the naphthalin that is abundantly found as a 
by-product in the gas works. 
The efficiency of creosote as a preservative of timber against 
the ravages of the teredo has, remarks the “ Engineering and 
Mining Journal,” been signally established by the recently-pub- 
lished report of a commission appointed by the Royal Academy 
of Sciences of Amsterdam to make a thorough investigation of 
the subject. This commission selected several of the ports of 
Holland in which to conduct their experimental trials, and sub- 
jected to their tests oak, red-fir, common fir, and pine, in pieces 
about 3 feet long and 12 inches square. They found that all 
external applications, such as coal-tar, paraffin varnish, mixtures 
of tar, resin, sulphur, &c., were absolutely worthless. Mechanical 
protection, by the use of nails, was found to be only partially 
efficacious, and, with the use of copper or iron sheathing, too 
expensive for ordinary use. Impregnation with various materials 
was also fully experimented upon, and, as against this element 
of destruction, with the single exception of creosote oil, all proved 
to be either completely or almost worthless. In this category 
are named sulphate of copper, copperas, acetate of lead, salts of 
mercury and arsenic, soluble glass, chloride of calcium, and 
paraffin oil. Only the blocks treated with creosote oil were found 
at the end of two years to have remained uninjured. The com- 
mission thereupon draw the conclusion that the only effective 
preservative agent for timber against the depredations of the 
marine boring-worms is creosote properly applied and of good 
quality. 
According to C. Fiirstenau in the “ Chemiker Zeitung ” the 
Austrian ultramarine manufacturers sophisticate their colours 
with three parts of gypsum, and lest the colour should appear 
too pale it is further mixed with glycerin or glucose or a mixture 
of both. This keeps the powder damp and renders the colour 
apparently deeper. 
Great industrial activity is being displayed by the German 
Distiller’s Association. At a general meeting it was resolved to 
establish and maintain a chemical laboratory, an experimental 
distillery, a school of distilling, a trade journal, a glass-blowing 
establishment for the manufacture of normal hydrometers, and 
an office for general intelligence. 
It is stated in “ La Lancette Beige ” that Mr. Edison has in- 
vented an ink which gives raised characters upon paper capable 
of being read by the blind by touch. 
The formation of mannite in beer is always a mark of the want 
of cleanliness and is particularly promoted by decaying wood. 
In such cases the sugar present enters not into the alcoholic but 
the mucic fermentation. 
