316 
POPULAR SCIENCE REVIEW. 
the same as petroleum — that is to say about 6d. per Prussian quart (1-45 
litres). The hourly consumption of carbolin, amounting, on an average, to 
30 grms., will cost about one halfpenny. As regards the price of the oxygen 
gas (an artificial air containing from 50 to 75 per cent, of oxygen), it is stated 
that this may be prepared on the large scale at a cost of 15 centimes 
per cubic metre (a little more than 35 English cubic feet). The carboxygen 
illumination is daily gaining ground in Cologne, Brussels, New York, and 
other places. This light is also employed now in some large hot-houses 
where plants and shrubs are exhibited, the colours of leaves and flowers 
seen by this light being seen exactly as in daylight, while there is no danger 
of injuring the most tender and delicate plants, as there is with other arti- 
ficial modes of lightning. 
Gustav Bischof in a Scotch Chair. — "We learn from the “Medical Press ” 
that M. Gustav Bischof has been appointed to the “ Young ” chair of Tech- 
nical Chemistry in the Andersonian University at Glasgow. M. Bischof is 
son of the late Professor of Chemistry at Bonn, and well known as the 
author of “ Chemical Geology.” 
Advantages of Infusorial Silica. — The “ Scientific American ” recently had 
an article on this subject. It says, that by mixing three to six parts of 
infusorial silica to one part of freshly burnt lime, and stamping the whole, 
after slightly moistening it, into a suitable mould, artificial stone of any 
desired form can be mad.e. Such stones become extremely hard, are im- 
pervious to water, are finer grained than cements of beton, can be used for 
gas or water pipes, and will take any colour. As there are large deposits 
of diatomaceous earth in various parts of America, this application for arti- 
ficial stone and cement is well worthy of consideration. By combining in- 
fusorial earth with native magnesite and chloride of magnesium, a cement 
is produced which is known in Germany under the name of i lbolith cement. 
The chloride of magnesium, obtained as an incidental product in salt manu- 
facture, is very cheap in some parts of Germany, and the occurrence of 
large deposits of magnesite renders this variety of cement available in Europe 
for many purposes. A fine glaze for earthenware is obtained by fusing 
infusorial earth with crude borate of lime, or boronatrocalcite. A variety 
of porcelain can be made by fusing infusorial silica with the borate of mag- 
nesia of the Stassfort mines. This kind of porcelain can be cast, pressed, 
and, if sufficiently thin, can be blown as easily as glass. It is capable of 
extensive use in the arts. 
Oxygen burnt with a Sooty Blame — The “Journal of the Franklin In- 
stitute ” contains an account of this experiment by Professor Thomson of 
Copenhagen. It says that heavy hydrocarbons, like benzol and oil of tur- 
pentine, burn with a very sooty flame ; with a very similar flame oxygen 
also burns in the vapours of these bodies. The experiment is made in the 
following manner : — Some benzol is warmed to the boiling-point in a long- 
necked flask ; the flask is closed by a cork with two holes, through one of 
which a glass tube of about 1 centimetre bore is passed, and through the 
other a tube somewhat narrower and bent to one side. When the vapour 
arrives at the orifice of the wider tube it is lighted, and then a tube, through 
which a slow stream of oxygen is flowing, is passed down into the flask 
through the flame. The oxygen tube is bent above, and its mouth is pro- 
