some salt. Then at last we have the gas
with which our jets and burners are
supplied, cold and invisible, but strongly affecting
our olfactory organs.

Every atom of this gas ("errors excepted")
passes through an apparatus called a station-
meter; it makes a fan rotate, and this makes
a wheel rotate, and this makes other wheels
rotate, and these make certain index hands
rotate in front of a graduated dial, by which
are denoted the exact number of cubic feet
of gas that have passed through. Then, from
this station-meter it passes to those vast
cylindrical structures which we see at all the
gasworks, some of them as much as a hundred
and fifty feet in diameter; they are called
gasometers, but a better name would be
gas-holders. Most of these have a kind of
telescopic action. Sliding up and down, according
to the quantity of gas they contain, they
are very full and very high in the afternoon
and early evening, when people are just about
to light up; rather empty and rather low in
the small hours of the morning, or about
daybreak, when gas-lights are few in number.
The gas passes through hundreds of miles of
iron pipes under the roadway of the public streets,
and through a still greater length of smaller
piping from these mains to the houses and to the
street lamps. The gas is under pressure in the
gasometer, in order that it may be forced into
the more distant as well as into the nearest
pipes; and this pressure is made greater in
some districts than in others, and at certain
hours than at others, according to the rapidity
with which the gas is consumed—a matter of
no small nicety connected with the economical
and efficient ordering of a gaswork.

This is gas making, stripped of technicalities,
and made intelligible as to its leading
characteristics. When the gas-light system
was first introduced, the gas was charged
at so much per flame or jet. It was perhaps
the best plan available at that time, but it was
uncertain: seeing that the size and form of the
burner have much to do with the quantity of
gas burned; and seeing, moreover, that the
companies' inspectors had but imperfect means
of knowing how long the gas was burning
after a shop was shut. There is rather a
nice bit of philosophy in the action of
gasburners. When gas is burned in a large flame,
a larger relative amount of light is obtained
from a given quantity than from a smaller
flame, other things being equal; because the
higher temperature produced enables the flame
to utilise the light-giving powers of the gas,
much of which otherwise gives out heat with
very little light. But this is not all. The
shape of the burner, or rather of the film of gas
which it shoots forth, has much to do with the
intensity of the light. The Argand burner has
a ring of very small holes; but a greater
quantity of light from a given quantity of gas
is obtained by using burners bearing certain
fanciful names—such as the fish-tail, the
cock-spur, the bat-wing, the swallow-tail, and the
union, in most of which the flame is spread out
into a kind of film or thin sheet. If we could
warm the atmospheric air before it feeds a flame,
the same consumption of gas would give forth
an increased light—on a principle analogous to
that by which the hot-blast produces a greater
result than the cold in iron smelting. This has
actually been done by Dr. Faraday and Dr.
Frankland, each of whom has devised a kind of
double glass chimney for gas-lamps, which enables
the lamp to warm its own air before feeding its
own flame.

These are the matters, or some of them,
which the legislature took under its charge
about eighteen years ago. It was thought that
the public were not sufficiently protected against
the powerful gas companies, and that the law
ought to have something to say to the price
charged for the article. Five years ago, another
act was passed, relating to the gas used in the
metropolis, and doctoring up the subject much
more elaborately than the former statute. It
gives a sort of exclusive sanction to certain
established companies. It divides the metropolis
into districts, awarding each district to
one particular company. It empowers the
Secretary of State to order inspectors to investigate
causes of complaint as to quality and
quantity of gas, and to enforce penalties against
the companies for any wrong-doing. It lays
down the rules under which new districts may
demand to be gas-lighted, whether at once
profitable to the companies or not. It declares
that the companies may demand that the gas
may be measured, or rather its consumption
measured, by meters; but it allows the consumer
to decide whether he shall use his own meter,
or rent one supplied by the company. It binds
the companies to be very liberal towards parish
authorities, in all that relates to street lamps—
much more than towards private consumers. It
defines what shall be considered good honest
gaslight. That is to say, " common gas, in a burner
consuming five cubic feet of gas in an hour, is to
give a light equal to twelve sperm candles, each
consuming one hundred and twenty grains per
hour; and cannel gas, from the like quantity, a
light equal to twenty such candles; and the
purity to be such as not to discolour turmeric
paper, or paper imbued with acetate or carbonate
of lead; and not to contain more than twenty
grains of sulphur in any form in a hundred cubic
feet of gas." It declares that no company shall
advance the maximum price of gas, if that price
had hitherto been four shillings and sixpence per
thousand cubic feet; but if the price had hitherto
been higher, then the maximum is declared to be
five and sixpence for common gas, and seven and
sixpence for cannel gas. And it contains a
number of minor clauses, intended to ensure
honesty and justice from everybody to everybody
else.

With the exception of a slight change made
in the next following year, the gas act of eighteen
hundred and sixty is that which is now in force.
If we are not all thoroughly enlightened, so
much the worse for us; the statute contains