THE NEW ZEALAND GAZETTE. 102

facture of fresh water at sea may be said to
have been until now an unaccomplished feat.

The other desiderata above alluded to are
these:-

When water, whether salt or fresh, is sub-
mitted to distillation, the condensed steam, in
stead of yielding, as might be supposed, a pure,
tasteless, and odourless liquid, has always an
almost intolerably nauseous, empyreumatic taste
and odour, which it retains for many weeks.
This taste and odour are so disagreeable, and
the water so produced being, as is the case with
ordinary distilled water, deprived of air by
boiling, is on that account, so heavy, indiges-
tible, and vapid, that the crews invariably refuse
it as long as they can obtain a supply from
natural sources, even though this may be of so
bad a quality as to endanger their health or
their lives, as evidenced by the report of the
Times own correspondent, in reference to the
water supplied to the crews of our ships in the
Baltic during the late war,

With a view to remedy these defects, chemi-
cal re-agents, such as alum, sulphuric acid,
muriatic acid, chlorine, chloride of lime, &c., to
be added to the distilled water, have been pro-
posed; but it is evident that the continuous and
daily absorption of chemical re-agents might,
and doubtless would, cause accidents of a more
or less serious nature, not to speak of the trouble
and care required in making such additions, an
excess of which might be attended with dan-
gerous, and possibly with fatal consequences;
besides, as a general rule, we have the authority
of Liebig to say, that the use of chemicals
should never be recommended for culinary pur-
poses, for chemicals are seldom met with in
commerce in a state of purity, and are frequently
contaminated by poisonous substances. On the
other hand, the pumps, ventilators, bellows,
agitators, the percolation through porous
substances, through plaster, chalk, sand,
&c., which have been proposed to
aerate the water obtained, and render it pala-
table, are of a difficult, inconvenient, or im-
possible application; they are costly, compli-
cated, bulky, or unmanageable; and as to
leaving the distilled water to become aerated
by the agitation imparted to it in the tanks by
the motion of the ships, the report of the cor-
respondent of the Times, above alluded to,
shows that this method is attended with but
indifferent success. I shall presently explain
why no system or method of aeration whatever
could be attended with success except under
certain conditions, and unless it be done in a
certain manner, conditions and manners realised
in my apparatus.

Another desideratum lost sight of in the en-
deavours which have been made to accomplish
the object (and it is a condition of extreme im-
portance) is to obviate, or prevent the deposit
of saline matter which takes place in the ap-
paratus when the limit of saturation has been
attained, and which, in a short time after use,
interferes temporarily at least, often prema-
nently, with the working of the apparatus,

renders frequent repairs necessary, and in all
cases eventually destroys it.

The expansion of metals by heat and their
contraction by cold, is another source of failure;
so much so, that it can be most truly asserted,
without fear of contradiction, that any fresh
water distilling apparatus for marine purposes,
in any part of which solder is employed, is ipso
facto, defective, and ought not to be trusted,
the soldered parts being sure to give way from
the cause just alluded to, and this perhaps (as
the event has unfortunately more than once
proved) at a time when the machine was most
wanted, its unsoundness thus creating the most
distressing sufferings, and putting the lives of
all on board in imminent jeopardy.

The question, which has hitherto been left
unanswered, and yet which must be integrally
solved before success could be hoped for, is the
following
一

To obtain, with a small proportion of fuel,
large quantities of fresh, Inodorous,
Salubrious, Aerated Water, without the
help of Machinery or the Chemical re-
agents, by means of a small and compact
Apparatus, incapable of becoming in-
crusted, or otherwise going out of order.

It is to the solution of this difficult and com-
plex problem that I now beg to call attention,
and I will proceed to explain the construc-
tion of the apparatus by which the object is
attained.

It is a known property of steam that it be-
comes condensed into water again whenever it
comes in contact with water at a tempera-
ture lower than itself, no matter how high the
temperature of that condensing water may be.
It is known that the sea and other natural
waters are saturated with air containing, a lar-
ger proportion of oxygen and of carbonic acid
than exists in the air we breathe. Experiments
which I undertook several years ago, with a
view to determine that amount, showed me
that whilst ordinary rain water contains, on an
average, about 15 cubic inches of oxygenised
air per gallon (of which 15 cubic inches of air
per gallon, about 6 cubic inches are carbonic
acid), sea water, owing to the various substances
which it holds in solution, contains only, on an
average, about 5 cubic inches of oxygenised air
per gallon, of which 5 cubic inches about 0.6 or
0.7 cubic inch are carbonic acid, or, in other
words, one gallon of sea water contains about
two-thirds less air than ordinary rain or river
water. I have also ascertained that air begins
to be expelled from such waters, when the tem-
perature reached about 130°. Fahr. Now,
my apparatus consists of two parts-an evapo-
rator and a condenser-joined so as to form one
compact and solid mass, screwed and bolted,
without solderings or brazings of any kind.
The evaporator consists of a space which is per-
vaded by steam-pipes containing steam, and
immersed in a certain quantity of sea water, a
portion of which is to be evaporated; steam, at
a pressure of about seven pounds, is then ad-
mitted into the steam-pipes of the evaporator,