318 
POPULAR SCIENCE REVIEW. 
power tested "by the standard sperm candles, and the following are the 
results: — Berlin, 15*5 candles ; Paris, 12-3; London, 12*1; Vienna, 9’0'; 
Edinburgh, 28-0 ; Manchester, 22-0 ; Liverpool, 22-0 ; Glasgow, 28*0 ; 
Aberdeen, 35-0 ; Greenock, 28*5 ; Hawick, 30*0 ; Inverness, 25*0 ; Paisley, 
30-3 $ Carlisle, 16 0 ; Birmingham, 15-0. Thus the gas supplied to Edinburgh 
and Glasgow gives more than twice the light of the gas provided for 
London. The above shows the average light given by the gas furnished in 
London ; but, in particular instances, it only equals nine candles. The gas of 
London, also, Prof. Frankland stated, is richer [fouler ?] than it ought to be 
in the sulphur compounds, and in burning gives off too much poisonous sul- 
phurous acid and other gaseous vapours injurious to health and property. 
London gas is now worse than it was many years ago, although its methods 
of manufacture have been cheapened by the discoveries of science, all new 
inventions in this direction having been eagerly taken up by the gas compa- 
nies, who, so far as is known, have not adopted a single invention which 
would benefit the consumer. The lecturer concluded by saying “ gaslight 
should have an illuminating power of twenty candles, below which no gas 
is fit for household use ! ” 
The description of Acetylene. — M. De Wilde describes a very interesting 
-experiment in which acetylene is resolved into its elements (if we may use 
such an explanation of the phenomena) by means of the induction spark. 
He gives the following as the best mode of performing the experiment. In- 
troduce the dry gas into a small eudiometer over mercury, and furnished 
with two platinum wires about four millimetres apart. At the passage of 
the spark, a light tuft of carbon is formed between the wires, and the 
action stops. Agitate the eudiometer, so as to cause the mercury to knock 
off the carbon, and the sparks which again pass will reproduce this phe- 
nomenon. The eudiometer is shaken as often as necessary for the continua- 
tion of the experiment. If operating with ten cubic centimetres of gas, 
from fifteen to twenty agitations will suffice ; the experiment will then 
proceed uninterruptedly. In ten or .fifteen hours all the acetylene will be 
decomposed. The remaining gas submitted to eudiometric analysis is found 
to be hydrogen. The acetylene should give its volume of hydrogen, but 
there is always a diminution of about a fifth, which may, perhaps, be 
attributed to the absorption of hydrogen by the deposited carbon, or perhaps, 
to the formation of some trace of condensed hydrocarbons. Vide Bulletin de 
la Societe chimique , vi. 267. 
Nature of the Earth eaten by the People of Borneo. — The Chemical News 
gives us the composition of the clay which is eaten so extensively by the 
natives of Borneo. It states that some years ago the manager of the 
Orange-Nassau colliery, near Zandjermasin, in the Island of Borneo, found 
that many of his workpeople (natives) consumed large quantities of a kind of 
clay ; a sample of this material was forwarded to Batavia for analysis, and the 
following i3 the result in 100 parts : — 
Pitcoal resin (organic matter volatile at red heat) 15*4 
Pure carbon „ „ „ 
Silica ,, ,, ,, 
Alumina „ „ ,, 
Iron pyrites „ „ „ 
Vide Chemical News , May 10. 
14-9 
38-3 
27-7 
3*7 
100*0 
