those of Moustier. But nearly all their weapons were 
light, and the deer-horn points replaced the flint points of 
an earlier epoch. 
The bow had become the predominant weapon, for 
henceforth nothing resisted man ; all fled before him, and 
hunting was no longer a struggle but a chase. There 
were two kinds of arrows ;: the little pointed arrow, not 
barbed, for small animals and birds, and the large dart 
with two sets of barbs, which was principally used in hunt- 
ing the reindeer. Light spears, terminating in a flattened 
point, darts with conical points, and long sharp poignards, 
which gave, when necessary, the finishing blow, completed 
the hunting equipment. I was nearly fo: getting the rally- 
ing whistle. It was a reindeer’s phalange, pierced near 
one end, with an oblique hole which did not go right 
through, and only penetrated to the medullary canal. By 
blowing on this hole as on a drilled key, one can, even to 
this day, extract shrill sounds. 
(To be continued.) 
THE NEW HYDROCARBON GAS 
sepia new hydrocarbon gas produced by Mr. Ruck’s 
process certainly promises to realise the concep- 
tion that has long floated in the minds of scientific men 
of turning the exhaustless store of heating power to 
account that lies ready to hard in water. Mr. Ruck 
appears literally, by the successful development of his 
invention, to have set the Thames on fire. At this 
present time, at the Battersea water-works, on the 
banks of the old river, near to Battersea Park, both light 
and heat may be seen and felt in the process of evolution 
from the decomposition of the water of its stream, and 
further light is added to the gas first produced by a very 
simple and uncostly extension of the process. until the 
illuminating power is raised to the intensity requisite for 
artificial lighting during the dark hours of the night. The 
Battersea water-works are now lit experimentally by this 
new forin of gas, an apparatus having been erected there 
to test and prove the efficiency and value of the method. 
Mr. Ruck’s hydrocarbon gas, it should be at once 
understood, differs entirely from the so-called “ air gases” 
that consist mainly of air impregnated with the vapour of 
some form of naphtha or petroleum, in the fact that its 
base is essentially a gas. The heating gas, which is the 
form first generated, is true honest hydrogen mingled 
with a little taint of carbonic oxide, and a small and prac- 
tically unimportant percentage of carbonic acid ; and the 
apparatus by which this heating gas is produced is re- 
markably ingenious and simple. Ordinary steam is 
brought through a pipe from one of the boilers of the 
engine house, and this steam is poured through a horse- 
shoe-shaped tube that passes through the red heat of 
a fierce coke furnace. In this tube it is superheated, 
or raised to a temperature which disposes its constituents, 
the oxygen and hydrogen, to dissolve their intimate 
alliance, and in that state it is passed on into retorts, 
also contained in a lower region of the same furnace, 
which are packed full of coke and fragments of iron. 
The steam is discharged into the interior of these retorts 
out of its own conducting pipe, so that it has to traverse 
their entire length amidst the masses of heated metal and 
coke, and during its journey it ceases to be steam. The 
oxygen attaches itself to the iron, and forms scales of 
black rust, and the hydrogen passes on free, with only a 
commingling with carbonic oxide and carbonic acid 
formed by the action of the disengaging oxygen upon the 
coke packing of the retort, and with certain sulphurous 
vapours that also issue from the coke. In this impure 
state the gas issues from the retort, and is carried to a 
purifying chamber containing oxid> of iron, which at 
once clears it from all the sulphur compounds, and it is 
Be us 
ins! 
te de aN by > Natal “®e : F 
Feb. 27, 1873] ‘ NATURE 329 
had some large spears, armed with flint, differing little from | then stored in a gas reservoir of ordinary form. In this 
state it is the “heating gas ;” that is, gas supereminently 
suited for all purposes where heat, without light, is re- 
quired, as, for instance, for gas stoves of whatever kind, or 
for boiling water, and generating steam. When the gas 
is taken from this reservoir, and discharged through an 
ordinary burner, it nurns with’the pale colourless hydrogen 
flame, streaked with a few lines. of yellow scintillations, 
ana of the characteristic pale greea colour of incandescent 
carbonic oxide. 
At the present time, with coals quoted in the London 
markets at 52s. per ton, this part of the affair, the pro- 
duciion of a heating gas out of water, at the cost of a 
very simple apparatus, a very small consumption of fuel, 
and with a demand for an incredibly small application of 
manual labour, seems to be the one that is most deserving 
of thought and attention. In the practice of the manu- 
facture at the Ba'tersea water-works, by the expenditure 
of one ton of coke for the interior of the retorts, and of 
two tons of coke for the support of the heat of the 
furnace, 133,000 cubic feet of gas are produced, that, to say ~ 
the least of it, is quite equal for all purposes of heating to 
coal gas in ordinary use, and that is as chemically endur- 
ing and perfect for storing in gasometers and for trans- 
mission to unlimited distances through pipes. In a direct 
experiment with the gas, tried by the writer, one quart of 
cold water was boiled in four minutes and a half by a jet 
of flame issuing from an orifice one-eighth of an inch in 
diameter, and under a pressure of three inches of water, 
without any arrangement for the concentration and pro- 
tection of the flame from chill and draughts. There was 
no provision on hand to measure the exact consumption 
of the gas, but the man who was engaged in the Labora- 
tory estimated it at about five cubic feet per hour. Now 
the cost of this gas at the works is found to be 7d. per 
1,000 cubic feet. In this experiment, therefore, the result 
was something like converting seven gallons of water at 
a temperature of 38° Fahrenheit, into boiling water for 1d. 
One thousand cubic feet at a cost of 7¢. would boil about 
50 gallons of cold water. At the works at the present 
time the steam is supplied independently from the boiler 
of the engine room. But this does not need to be taken 
into consideration, because the waste heat of the retort 
furnace is more than enough for the production of the 
steam, and in ordinary circumstances will be used, as a 
matter of course, for the purpose. 
When it is desired to use the gas for lighting purposes, 
it has to be further prepared and manipulated. The 
“heating gas” from the gasometer is made to bubble 
through a reservoir containing rectified petroleum at a 
specific gravity of about 0680. It then passes at once 
into the pipes for circulation and consumption, and issues 
from these burners a very excellent gas, equal in illumi- 
nating power to 16} candles with a consumption of 5 cubic 
feet an hour in an Argand burner. The cost of the gas 
in this form is a trifle less than Is. 8d. per 1,000 cubic feet, 
and the saving in the manufacture over ordinary coal gas 
with coals costing 26s. per ton, is estimated to be 40 per 
cent.—in exact figures 1s. 8d. per 1,000 cubic feet against 
2s. 4d. per 1,000 cubic feet. One thousand cubic feet of 
the heating gas require a gallon and a half of the petro- 
leum to convert them into illuminating gas, but they are 
considerably increased in volume by the conversion— 
133,000 cubic feet of “heating gas” become 165,000 cubic . 
feet of “ illuminating gas” after it has been passed through 
the petroleum. Arrangements have been made for the 
purchase of several millions of tons of crude petroleum 
at a price which will represent a cost of 6d. a gallon after 
rectification. 
Some rather severe experiments have been already 
tried to test the power of the illuminating gas to retain 
its full charge of carbon “after travelling through long 
distances of delivery at low temperatures, and the report 
of the testing engineers is that so far the experiment was 
