popular; folk like to see what they are eating;
and the revelations which came to light some
years ago have not helped their consumption,
though none need be afraid of what is sent
from Australia, for good joints are the cheapest
things we can put in. Necessity secures our
honesty. Then there is Baron Liebeg's
extract; but most people would rather have a cut
at a juicy beefsteak than drink a spoonful of
extract. We are, however, making extract,
and doubtless a limited market will be found
for it. Mutton and beef may be salted. This
we are doing. Beef hams, mutton hams, rolls
of beef, sides of mutton salted and spiced, are
to be packed in iron tanks, into which tallow is
to be poured, to keep the meat from getting
hard and dry, and you in English markets are to
buy spiced and smoked meats, hitherto sold at
Italian shops for two shillings a pound, for six-
pence. But this, appetising as it is, and
splendid for breakfasts and lunches, will, we
fear, not satisfy the paterfamilias of middle
life as his cut-and-come-again dinner joints.
We in Australia want, and you in England
want, that the aforesaid pater should be able
to go and look out a leg of merino mutton—fed
on our plains, and which, perhaps, grew the
most perfect wool in the world—or a sirloin of
beef fattened on salt bush, and, being able to
pinch it with his fingers, and see that it is all
right, order it to be sent home, to feed his
rough school lads or his sweet English maids.
At ihe head of a pretty little valley, called
La Croza, near Sydney, New South Wales,
stands Mr. Mort's refrigerating establishment.
To this refrigerating or freezing process we
look as a possible means of giving you our
fresh meat. Frozen meat is not a new thing,
but the difficulty is to freeze and keep it frozen
for a three months' voyage, and that through the
tropics. Mr. Mort has patented a process,
discovered by a Mr. Nicolles, by which it is
believed this may be done.
The inventor, in his application to the
Supreme Court for a patent, says, "The invention
is an application of Professor Faraday's discovery
of the liquefaction of certain gases by
pressure, and capacity of such gases for
absorption of heat in their return from liquefaction."
The apparatus erected at La Croza, and
intended to be used on board ship, is describable
somewhat as follows:
The material used is, the common liquid
ammonia of commerce; this being greatly
rectified is put into cylinders called separators,
the quantity of absolute ammonia in such
vessels being indicated by glass gauges. From
a small steam boiler, steam is led by a coil
which passes into a separator: the object of
using the steam, being to heat the ammoniacal
solution in the separator, and so to cause the
ammonia to be volatilised, or in other words
resolved into gas. So gasified, the ammonia is
drawn off from the boiler, and conveyed by a
series of pipes through a number of coils into
a bath or tank of water (which may be on the
deck of the ship). The object is to condense
the aqueous vapour by which the
ammonia is accompanied. The gas thus dried
is then forced by steam into an iron cylinder
immersed in a bath (also on deck), and there by
pressure on itself, being a non-permanent gas,
it becomes liquefied. This last vessel is called
the liquid gas receiver. From this receiver,
the gas in a liquid state is passed by pipes into
the outer compartment of the meat receiver, an
immense double cylinder as capacious as may
be required. This meat receiver is made with
double casing, its walls perfectly tight, to contain
the liquefied gas, supplied from the liquefied
gas receiver. The whole vessel is surrounded
by some good non-conducting substance, as
charcoal, felt, or gutta-percha; and that is enclosed
again in a wooden covering, varnished or painted,
so as to exclude all moisture. The inner cylinder
rests on the bottom of the outer, leaving a
space at the top of about two inches. At the
ends are holes large enough to give ingress
and egress to men for stowing, unloading, &c.
These openings are fitted with wooden coverings
fitted round with gutta-percha.
Having thus tried to give an idea of the apparatus,
let us endeavour to describe the manner
of using it. The gas having been drawn out
of the separators, the heated water is forced
through two coolers, and from the coolers passes
on by a pipe into an iron cylinder called the
reabsorber, which is immersed in a water tank.
The separator being emptied is again supplied
with ammoniacal solution, and the process is
repeated; the reabsorber now containing but a
very weak solution, is prepared to receive the
gas coming to it from the compartment round
the meat receiver. Let it be remembered that
ammoniacal gas has so great an affinity for
water, that water at sixty degrees Fahrenheit
will take up six hundred and seventy times its
volume of gas. The consequence of this is
that when, by opening a stop cock, admission
for the gas into the water is obtainable, it rushes
in with great violence, passing from its state of
liquefaction into a gaseous form, and carrying
with it all the caloric or heat contained in the
meat it has been surrounding.
It is in this transition, when the liquid
expands into a gaseous state, that the freezing
or complete refrigeration takes place. Through
special details in the apparatus, there is no loss
whatever of the chemical substance employed.
The compartment round the meat is filled with
the icy current from time to time, until all the
meat, &c., placed within is frozen to the
required degree of intensity. The ammoniacal
gas is capable of freezing to one hundred
degrees below zero. One hundred tons of meat
can be frozen in twelve hours by the apparatus
now erected, which, as at present constructed,
would take up about thirty tons measurement
on board ship. The meat frozen thus for
months, when allowed to thaw, is found to have
lost none of its flavour, and will keep as long as
meat newly killed. Meat and fish kept for
six months have been used at the clubs and
government houses, and have been pronounced
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