time that it whitens the whole compound,
and sometimes enables flour of an inferior
quality to produce loaves of "the best bread."
When the Lancet published its analysis of
bread, purchased at random from many
shops, there was found scarcely a specimen
from which alum was absent; and we do not
know of any change that has been made
since that time in the practice of the bakers.
It is said in the Encyclopædia Britannica, that
it is common to put as much alum into the
bread as salt, two pounds and a quarter to
the sack. This would yield one hundred and
fifty-seven grains to a loaf, a serious quantity.
Experiment has shown that less alum than
thirty-one grains to a loaf would not affect
the bread at all, while this quantity—the
lowest that can be assumed— yields a weekly
allowance of astringent matter to the British
consumer that cannot fail to have a slow
and hurtful influence upon his organs of
digestion.

According to the statement of MM. Dumas
and Kuhlmann, the use of blue vitriol in
bread is almost invariable in France and
Belgium, so that our neighbours fare worse
than ourselves. For although the proportion
of this poison used for producing sponginess
is very small, the use of a deadly thing is
placed in careless hands, and it would be well
if the French took as much care for their
bread as for their sweetmeats.

We should be glad to hear a tumult and
rebellion against alum in our bread, and we
should very much like to see private English
families acting on their own account, and
spreading dismay among all dishonest tradesmen,
by testing for themselves the purity of
many things that they consume. There is a
penalty against the adulteration of bread, but
the best penalty would be the loss of custom
that would follow upon prompt detection of
offence in private families. The testing of
bread is very easy. Alum is the great object
of search; chalk, carbonate of ammonia, soda,
and potash, are added only in extreme cases
of fraud, to neutralise the acid that will form
in bad or stale bread. A writer in the Medico-
Chirurgical Review tells of his experience
among the crew of a vessel who were all
seized with a similar disorder, that was
traced eventually to the serving out of certain
biscuits bought at Wapping. Each one of these
biscuits contained eighty-five grains of chalk.
Such cases are extreme. It is against alum
that we have to direct the main point of our
attack, it we desire, in these good days, while
we are getting cheap bread, to have it pure
into the bargain.

If any one desires to test the honesty of
bread, let him cause it to pass through the
ordeal either of fire or water. The ordeal by
fire consists in placing a piece of bread
accurately weighed in a Cornish crucible, and
subjecting it to lively and continued heat. If
it be pure, it will consume and leave a residue
of not more than two per cent. in the shape
of a very soluble white ash. Of that ash, one
half will be dissolved in water, and the rest,
on adding muriatic acid to the water, will
dissolve without effervescence. If there be
chalk, or carbonate of magnesia, potash, or
soda in the bread, there will be effervescence
when the residue of the ash dissolves under
the influence of muriatic acid. Other
adulterations will be revealed by the excess over
two per cent. of ash, and the dissolved ash
may be tested on some plan that appertains to
the ordeal by water. The trial by water is
the following:—

Soak about six ounces of bread in two
ounces of distilled water, for an hour or longer.
Squeeze the sop through a coarse linen cloth.
Let the grosser particles subside from the
liquor: if there be grains of potato starch
among them, they will be distinguishable. Pour
off the clear liquor from the condiment, and
then evaporate it to about half its bulk. The
mysteries of the bread, if there be any, will be
contained in the resulting fluid. Test a part
of it, by adding a few drops of strong liquor
of ammonia; and if there be alum in the bread,
there will be a white powder precipitated. If
you suspect the French mystification of blue
vitriol, test another portion with prussiate
of potash; when, if there be copper in the
bread, you will get a rose-coloured or chocolate
precipitate. If the effect of nitrate of baryta
and nitric acid be tried on another portion of
the fluid, they will produce results of a decided
character, if there be in the bread any soluble
sulphate, alum, plaster of Paris, or blue vitriol.
If the sop was made with wholesome bread,
none of these tests will produce any marked
result upon the liquor. A slight trace of
alum— if it be a very slight response to active
testing— will tell rather of a chance impurity
in the salt than of a wilful act of adulteration
by the baker. The sop after straining, if
exposed in a crucible to heat, should leave not
more than one per cent. of ash. Good flour
when burnt should not leave more than, at
most, two per cent. of ash; and water, in
which it has been soaked, should yield no
precipitate on being tested with acid, nitrate
of baryta, prussiate of potass, or solution of
ammonia. In a quartern loaf there is an ounce
of salt. It surely would suffice.

We will pass now to a few other topics.

There are ready means of testing to a
certain extent the purity of wine; and since
that is one of the articles in which the British
consumer suffers wrong to a considerable
extent, it may be worth while to name them.
Pure wine ought not to leave a pink stain
upon paper. MM. Jacob and Nees von
Esenbeck give this advice. Add to a glass of wine
alum and carbonate of soda. The precipitate
in pure wine will be very slightly coloured,
but in the case of adulteration it will be more
or less pink or violet. Chevalier says,
saturate red wine with caustic potash; it will
change to bottle green, and after a time, if pure,
to brownish green or brown. If it contain