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occupy hundreds of pages。 Those cited are exemplars
indicating the trend of ideas belonging to different
nations； epochs； and the diversity of materials。 They
can also be considered as object lessons which conclusively
demonstrate the dissatisfaction always existing
in respect to the constitution and modes of ink admixture。
Many of them are curious and are reproduced
without any amendments。
〃Indian ink is a black pigment brought hither
from China； which on being rubbed with water；
dissolves； and forms a substance resembling ink；
but of a consistence extremely well adapted to the
working with a pencil…brush； on which account it
is not only much used as a black colour in miniature
painting； but is the black now generally made
use of for all smaller drawings in chiaro obscuro
（or where the effect is to be produced from light
and shade only）。
〃The preparation of Indian ink； as well as of
the other compositions used by the Chinese as
paints； is not hitherto revealed on any good authority；
but it appears clearly from experiments
to be the coal of fish bones； or some other vegetable
substance； mixed with isinglass size； or other
size； and most probably； honey or sugar candy to
prevent its cracking。 A substance； therefore； much
of the same nature； and applicable to the same
purposes； may be formed in the following manner。
〃Take of isinglass six ounces； reduce it to a
size； by dissolving it over the fire in double its
weight of water。 Take then of Spanish liquorice
one ounce； and dissolve it also in double its weight
of water； and grind up with it an ounce of ivory
black。 Add this mixture to the size while hot；
and stir the whole together till all the ingredients
be thoroughly incorporated。 Then evaporate away
the water in baleno mariae； and cast the remaining
composition into leaden molds greased； or make
it up in any other form。〃
〃The colour of this composition will be equally
good with that of the Indian ink： the isinglass
size； mixt with the colours； works with the pencil
equally well with the Indian ink； and the Spanish
liquorice will both render it easily dissolvable on
the rubbing with water； to which the isinglass alone
is somewhat reluctant； and also prevent its cracking
and peeling off from the ground on which it is
laid。〃
* * * * * * *
There is found in small currents near the Baltick
Sea； in the Dutchy of Prussia a certain coagulated
bitumen； which； because it seems to be a juice
of the earth is called succinum； and carabe； because
it will attract straws； it is likewise called electrum；
glessum； anthra citrina； vulgarly yellow amber。
〃This bitumen being soft and viscous； several
little animals； such as flies； and ants； do stick to it；
and are buried in it。
〃Amber is of different colours； such as white；
yellow and black。
〃The white is held in greatest esteem in physick；
tho' it be opacous； when it is rubbed against anything；
it is odoriferous； and it yields more volatile
salt than the rest。 The yellow； is transparent and
pleasant to the eye； wherefore beads； necklaces；
and other little conceits are made of it。 It is also
esteemed medicinal； and it yieldeth much oil。
〃The black is of least use of all。 （Sometimes
used by the ancients in making ink。）
〃Some do think that petroleum； or Oil of Peter；
is a liquor drawn from amber； by the means of subterrenean
fires； which make a distillation of it； and
that jet； and coals are the remainders of this distillation。
〃This opinion would have probability enough in
it； if the places； from whence this sort of drogues
does come； were not so far asunder the one from
the other； f or petroleum is not commonly found but
in Italy； in Sicily； and Provence。 This oil distils
through the clefts of rocks； and it is very likely to
be the oil of some bitumen； which the subterranean
fires have raised。〃
* * * * * * *
There are various processes for obtaining gallic
acid； one of which is to moisten the bruised
galls and expose them for four or five weeks to a
temperature of 80 degrees Fahr。； by which a mouldy
paste is formed； which is pressed dry and then digested
in boiling water； which after evaporation
yields the acid； and mixed with the solution of
green copperas； makes the； ink。 A quicker process；
however； is to put the bruised galls into a cylindrical
copper of a depth equal to its diameter； and
boil them in nine gallons of watertaking care to
replace the water lost by evaporation。 The decoction
to be emptied into a tub； allowed to settle；
and the clear liquid being drawn off； the lees are
emptied into another tub to be drained。 The green
copperas must be separately dissolved in water；
and then mixed with the decoction of the galls。 A
precipitate is then formed in the state of a fine
black powder； the subsidence of which is prevented
by the addition of the gum； which； separately dissolved
in a small quantity of hot water； combines
with the clear black liquid。 Besides its effect in
keeping the fine insoluble particles in suspension；
the gum mucilage improves the body of the ink；
prevents its spreading or sinking too much into
the paper in writing； and also acts beneficially by
forming a sort of compact varnish in it； which
tends to preserve its colour； and shield it from the
action of the air。 If； however； too much mucilage
is used； the ink flows badly from quill pens； and
still more so from steel pens； which require a very
limpid ink。 The addition of sugar increases the
fluidity of ink； and permits the quantity of gum to
be increased over what it would bear without it；
but； on the other hand； it causes it to dry more
slowly； and besides it frequently passes into vinegar；
when it acts injuriously on the pens。 The dark…
coloured galls； known as the blue Aleppo ones； are
said by Ribaucourt； and others who have given
much attention to the ingredients for ink…making
to be the best for that purpose； and they are
generally used by the best makers。
〃From their high price； however； and that of
galls generally； sumach； logwood； and even oak
bark are too frequently substituted in the manufacture
of inks； but it need scarcely be said always
injuriously。 Ink made according to the receipt
given above is much more rich and powerful than
many of those commonly made。 To reduce it to
their standard one half more water may be safely
added； or even twenty gallons of tolerable ink may
be made from the same weight of materials。
Sumach and logwood admit of only about one…half
or less of the green copperas that galls will take；
to bring out the maximum amount of black colour。
The colour of black ink gradually darkens in
consequence of the peroxidation of the iron in it on
exposure to the air； but it affords a more durable
writing when used pale； its particles being then
finer； penetrate the paper more intimately； and on
its oxidation is mordanted into it。 It is advisable
so soon as the ink has acquired a moderately deep
tint； to draw it off clear into bottles and cork them
well。
〃According to the most accurate experiments
on the preparation of black writing inks； it appears
that the proportion of the green copperas ought to
be； and not to exceed； a third of the decoction of
galls used； but the proportions used vary according
to the practical experience of ink…makers； who
have all receipts of their own； which they deem
best； and； of course； keep secret。 In the precipitate
an excess of colouring matter； which is necessary
for its durability； is preserved in it。 The
blue galls alone ought to be employed in making
the best quality of black ink。 Logwood is a useful。
ingredient； because its colouring matter unites
with the sulphate of iron and renders it not only of
a very dark colour； but also less capable of change
from the action of acids or of the atmosphere。
Many attempts have been made by amateurs to
make a good permanent black ink。 A good story
is told of Professor Traill。 He had succeeded；
after a long series of experiments； in producing an
ink which he deemed to be in all respects A 1；
and which resisted the action of all acids and
alkalies alike。 The pleased savant sent samples
of it for trial to several banks and schools； where
it gave general satisfaction； but； alas； an experimenting
scribbler； thoughtlessly or otherwise； applied
a simple test undreamt of by the Professor；
and with a wet sponge completely washed off his
'indelible；' and thereby finished his career as an
amateur ink…maker！〃
* * * * * * *
〃Nicholson； in his Dictionary of Chemistry； an
old but valuable work； says that Ribaucourt found
vitriol of copper； in a certain proportion； to give
depth and firmness to the colour of black ink；
but； from whatever cause； this has not taken a
place among the commonly…used ink…maki