Method of Preserving Water Sweet

A new and easy METHOD of preserving WATER sweet, for the USE of SEAMEN
in SEA VOYAGES, and of purifying it when stinking.
IT is well known that water cannot be-
come putrid, unless it contains animal
and vegetable substances; and as this is 
the case with all river water, it follows
that this water, which is generally used on
board of ships, is subject to become putrid
and nauseous, more or less, in proportion
to the quantity and quality of the animal
and vegetable matter contained in it.
    Another cause of corruption is owing to
the dissolving property of water; so that
it often happens, that though the casks be
filled with pure spring water, yet the wa-
ter, by dissolving the impurities which may
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be found adhering to the casks, and be-
coming impregnated with them, or even
with the substance of the wood itself, will
become putrid after a certain time.
    The principal article, by the means of
which Mr. Lowitz preserves and purifies
water, is charcoal dust; and from a great
variety of experiments, the following par-
ticulars are deduced for the practical ac-
complishment of an object so very impor-
tant to the seafaring people.
    The charcoal must be pounded very
finely, and the powder must be kept clean,
and as free as possible from dust, smoke,

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or other impurities; but the quality of
the wood of which the charcoal is made
needs not to be regarded, provided it be
well charred.--Mr. Lowitz finds that even
fossil coal, when well charred and pow-
dered, will answer for the purpose; but
he does not mean to recommend the use
of it, on account of the metallic minerals
which are frequently mixed with it, be-
sides other reasons.
    About three drachms of charcoal dust 
will preserve four ounces of common river
water, or will purify it when actually
stinking; but if a little acid be added,
then a much smaller quantity of charcoal
will do.
    Any of the mineral acids will produce
the effect, and even some salts; but the
vitriolitic acid is to be preferred, princi-
pally on account of its having no smell.
    In order to preserve fresh water, the
casks must be previously well washed and
scoured with sand or charcoal dust. After
having been filled with the river water,
put as much vitriolitic acid into it as is
just sufficient to render the water slightly
acid: then add about eight pounds weight
of charcoal dust to each cask; and as the
charcoal dust naturally falls to the bottom
of the casks, it should be stirred with a
stick at least once a-day, so as to let it
come into contact with as much water as
possible; and this is all that needs be done
to prevent the water acquiring any bad
smell or taste.
    When the water is to be used, it should
be filtered through a flannel bag, which
must be ready at hand, and a proper stand
for it may be easily contrived. This fil-
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tration serves only to separate those finer
particles of charcoal, which, by swimming
in the water, give it a blackish appear-
ance.
    It is very remarkable that, if water be
rendered just sensibly acid by mixing a 
little vitriolitic acid with it, the addition
of charcoal dust will remove the acidity.
    In order to purify the water which is
actually stinking in the casks, proceed in
the same manner as in the preceding oper-
ation; viz. first, put some vitriolitic acid
into the cask, and the[n] as much charcoal
dust as upon trial will be found sufficient
to remove the bad smell. In case that
neither vitriolitic nor any other acid can
be had, then charcoal dust alone is suffi-
cient to purify the water: but in this
case a greater quantity of it must be used;
perhaps three time as much as when the
acid is employed.--This purified water
must be also filtrated as above.
    In this manner the operation is soon
performed; ten minutes, or a quarter of
an hour, being more than sufficient time
for it.
    To preserve the water which has been
thus purified, when it is not immediately
used, it must be removed into clean casks;
otherwise it is apt to become putrid again
in a short time.
    It is almost needless to remark, that as
the waters of different rivers, in different
climates and seasons of the year, are im-
pregnated with various proportions of
animal and vegetable matter, so the quan-
tity of charcoal dust which must be em-
ployed to preserve and purify them, must
be more or less in proportion.