The Liverpool Standard and General Commercial Advertiser.
Liverpool, Merseyside, England, 1838-02-02 00:00:00

:MEETINGS OF CREDITORS

FF.BRUNAY. . _ _ _ HOUR
5. Leonard Albin, (proof) —Clarendon Rooms,. 11
5. Robert Graves _ - • .. Ditto 1
7. 8,-13nehanan and D. Laird, (proof; Lowndes'and Robinson's, :2
8. William Franklin Mr. Holden's, 1
8. Abraham W. Cr.llaid Clarendon Rooms, —1
Samuel Burke, Ditto 1
9. John 1-Macdougal • Radclitru and Co.'s 1

LIVERPOOL MECHANICS' INbTITUTION.

LECTURES ON CHEMISTRY

Qn.Wednesday evening Dr. Kane delivered his seVenth.lec-
ture to a numerous audience. •
We may effect the analysis of muriatie acid by putting in
contact with the liquid solution any substance which has a
powerful affinity fur chlorine, in which case the chlorine will
be withdrawn from the acid and the hydrogen will be set free,
the result being that the muriatie acid gas is decomposed,
—one of its elements passing to the metallic body, and
the other being liberated may be- collected in an isolated
state. For instance it we pour upon a small quantity of tin a
small quantity of muriatie acid, a very violent action takes
piaie, and we shall find upon applying a taper Oa; hydrogen
is liberated:- IslOw by Means of this simple experiment we se-
parate. moriatic acid into hydrogen and chlorine, the latter of
.which combines with the zinc. The chlorine forms with the
zinc a compound soluble in water and which can be crystallized.
Consequently by taking a giverrquantity of liquid Inunatic acid
and zinc, by weighing thechl:iri;le ofzinc, and hydrogen. we shall
find the numbers in which hydrogen and chlorine unite to form
muriatie acid. An analysis produCing still more remarkable re-
sults can be made by means of aii apparatus consisting of a
flask containing a quantity of common salt, into which (the salt
having been previously melted and broken into; large lumps to
• prevent the violence of the action) a quantity of dilute sulphuric
acid is introduced; a rapid dec./1111)681[ton of the sail ensues and
muriatie acid being evolved- is conducted by means of a tube
into a vessel containing sulphuric acid. Being by this means
deprived of its moisture, the dry gas is conducted into a tube
containing a quantity of the metal sodium which it passes over.
The heat of a spirit lamp being being applied to the surface of
the tube beneath the sodium, the chlorine of the muriatie acid
contbiues with the sodium so energetically us to produce combus-
tion, and hydrogen is emitted from the other end of the tube.
,By this process a white powder is formed from the union of the
chlorine with the sodium which is nothing else but common
salt, (chloride of sodium). It is evident that it will only be
necessary to weigh the original substances and the products, to
arrive at the actual numbers. .

It is a tact well worthy of attention that the bodies which
which most resemble each other in their nature ate most con-
stantly aseoeiated with each other in nature ; thus we find
chlorine, iodine, and bromine, associated together as well as
manganese and iron. lodine.is a substance of intense interest, as
its discovery shows the great importance of observing with ac-
curacy all the. phenomena wince occur in the arts, even in the
progress of abstract science. •lieliiie was not discovered by any
chemist, but by a manufacturer, and Under the ciitannstances
its which it is formed, ib could only be discovered by a manu-
facturer. It exists' only in nature in soda alkalies, and even in
these in very minute quantities. It is one of those substances
which diffused originally through an immense mass of water is
by the means in winch this water is used in the arts gradually
concentrated into the shape in which it is obtained. M. Cour-
tois observing that the iron pans in which he boiled Up his kelp
for the purpose of soap-making was corroded to a great extent
by a substance which he could not find accounted for or described
in any work in' chemistry, took some of the substance to Guy
Lusac who decided it to be a new substance. We owe the ge-
neral illustrations of the prinvidles of lodine to Gay Lusac, as
well as to. Sit Humphrey Davy, hut we must nut forget that the
discover v of lodine was made by Courtois the soap manufac-
turer, of Paris, and that it could not have betordiscoveren but iii
the 'operations of such a manufactory as that which he con-
ducted. the geoerality of sea water contains iodine, as it also
does a great quantity of chloride of sodium or common salt.
Incline exists in sea water under:the form of iodide of magnesia,
but its quantity is so exceedingly minute that it would be lin-
possible•by ordinary analysis to detect iodine without having
first concentrated the sea water to an extraordinary extent.
This conrentiation is carried on to a great extent by the aquatic
plants which exist in the water, and when the plants are col-
lected and burnt to ashes, we find they give to us the salts
I,,::ivelic.ii:„h„
pi:
,ree,vi
,i previously
_which-Iwiseteduseinit'ivattleier, artspar and
tlypurecoannutil ie tricaer.t—
-' ly
oe p6aluci Om of the iodine may be- simply 'iilustrated. We
is 'T
liall, not, however, have- recourse
i
,Flh'j.aining it as in the arts, but sill suppose that from the mass
or .kelp the reariodine-constituent has been eliminated, and that
are have only to decompose this substance to set the iodine free.
If noir into a retort upon some iodide of potassium, a quan-
tity of sulphuric acid, and apply heat, we get a very interesting
action. • After a short time &sirifs-tepee will distil overiuto a re-
tort which condeuses to a solid state. The reaction which takes
place is siiiiple. One equivalent of the oxygen ofthe sulphuric
acid unites with the potassium to form potash, and both sot.
phurous acid and -iodine is set free. The iodine of magnesia is
used in commerce; in Order to produce the iodine. The purple
colour of the substance, procured it the name of iodine, from
the Greek. When iodine is heated it at first melts, and after- •
wards is converted into vapetir. • By a reduction of the temper.;
,ature the iodine again solidifies, and is deposited inoclahedral
crystals. lodine is remarkable as being the only one of the
rom-metallic bodies possessing aanetallic lustre. It is sparingly
soluble in water which it colours a pale brown. It is much more
soluble in spirits .of wine, 'and: the tincture of iodine is a most
important medicinal agent. One of the most important uses of it
is, in cases of glandular swelling in the neck, to which the in-.
habitants of some parts of Derbyshire, and the ueighbourhood
of the Alps are subject. Burnt sponge was found to be an ex-
cellent remedy in theie cases; and after the discovery of iodine
it occurred to the medical men at Geneva, that sponge being a
sea plant might contain iodine. This being found to be the
fact, led to_ the employment of iodine in these cases, for which
sponge was ceusidered a specific, and we now count iodine
amongst our most valuable medicines. It is a substance most
easily' recognised.. 411 bas a remarkable action on starch, with
which it forms a purplish blue compound, called iodide of
starch. An excellent sympathetic ink for secret correspond-
ence may thus be formed. Thus, if certain characters be traced
with a solution of starch on paver, when di y, the characters will
be invisible, 'out upon brushing them over with a solution of
iodine, they immediately show themselves of a blue colour. By
€;mobiying, a weak alkali the writing again becomes invisible,
in consequence of the iodine lea'ving the staa eh to combine with
the alkali, but by neutralizing the alkali with an, acid the iodine
will again unite-with the starch, and the writing wilt
:reappear.
If' we allow a little of the blue .iuditle of starch to buil over a
spirit lamp, the colour will risappear, bud upon the cooling of
the compound
,it will
,again reappear, though not so deep a
colour. The rationale, of this is yet a mystery, but is supposed
to be owing to smile species of ffecomposition. lodine enters
into a number of combinations with the metals, but it does not
unite with them so powerfutly as chlorine, and, consequently,
• we cannot uuderordinary circumstances obtain the combina-
tions, except by indirect methods. If we take a solution of
corrosive sublimate, and add to it a solution of iodide of potas-
sium, we obtain a red precipitate of an exceedingly brilliant
hue, indeed, it is one of the most beautiful reds which we know
of for surpassing-vermillion. This substance is a. eombination
of iodine with quicksilver, called iodide of _mercury.. In.
making this experiment it is requisite to be cautious in adding
the iodide of potassium, for, if it be used in excess, the purple
again disappears, being immediately re-dissolved. When the
iodide of potassium is added to.a solution of lead, a precipitate
is formed of a rich Canary colour. The iodide of Mercury and
the iodide of lead are excellent tests for iodine in a state of
combination, and starch is an -ekcellent test for it wh.re it is
tree. If we mix a little of the' iodide-of potassium milli s.trch
there will be no change of colour, because the itlline has a
weaker affinity for the starch than it has for the potassioar ; but
if a small quantity of an acid be adiled, the alkali unites with
it, leaving the iodine free to unite with the starch, which, it
does, and Produces the blue colour. By these means we are
enabled to prove the presence of iodine without the possibility
of a shadow of doubt lodine unites with nitrovn, and be-
comes highly explosive. The iodide of nitrogen is a brown
powder, and if it be struck slightly with a stick, it detonates
with a loud noise.

Broinine is generally associated with ibdine, but it, existsin
still smailer.quantities: It was discovered by Baiard, the cele-
brated manufacturing chemist of Montpelier. It is remarkable
as occupying an intermediate p osition between iodine and chlo,
rine. We have seen that chlorine is gaseous, and thatiodine
is solid. Now Bromine is a deep red liquid. Not only in its
liquid state,. but in every other property, dues brownie stand,
exactly halt way between chlorine and iodine. The odour of
bromine is far worse than that of chlorine, from which circum-
stance it has derived its name. Bromide evaporates so fast,
that it cannot be kept in the liquid slate, unless the bottles in
which it is contained are immersed in water. The instant a
drop of bromine falls upon potassium, as energetic coMbinatiou
takes place, accompanied by flame and a loud explosion. In-
deed thil substance ranks only interior to chlorine in its com-
bination with the metals.

A substance which possesses some interest in a scientific point
of view, but which has not yet proved of such practical import-
ance, is fluorine. There has loug been knawn in this country
a mineral called fluor or Derbyshire spar. it eutisists of lone
combined with a peculiar acid. After Sir Humphrey Dv"y
had suggested the theory now generally adopted respecting the
nature of chlorine, he proposed to admit fluorine as a 'separate
element. F'luate of time is easily decomposed. This is done by
pouring sulphuric acid into a vessel containing powdered flaate
of lime. The sulphuric acid unites with the lime, and fluorine is
expelled, but as fluorine unites with the silicon of glass vessels,
turning out the oxygen, it is impossible to collect it pure by such
means; but the Rev. Mr. Knox of Dublin, has succeeded in.
obtaining it pure in vessels of tluur spar constructed in a pecu-
liarimanner. •Ad -he has been able, however, to'determine re-
specting it is, that it is gaseous and colourless. Indeed we, as
yet,' know very little more about its properties or combination,
except-the fluoi ide ofhsjlrugen a htl its actiougupon glass; • -
• floe of the most e.xteusively dist rihuted substances in nature
is that of which sarid, quartz rock, and rock crystal, are, com-
posed. These rocks, as well as the flints, tumid in such abund-
ance in sonic parts of the country, are found to consist of a sub-
stance, which has recently been discovered to be an acid, called
silica, or silicon, combined with oxygen. Silica consists of one--
half its weight of oxvgtn united too-the base, and possesses very
powerful affinity for alkalies or bases. When silica has once
been funned, it is insoluble in water, and the way,'theretbie, iii
which we form its combinations is„ by melting silica with its
bases. Common clay is one of the most remarkable of the sili-
cates, —it is a combination of silica with atutnina or pure clay.
By combining silica with- an alkali and melting it with an in-
tense heat we obtain glass. The glass made at Prague stands
Item much better than that made in this country, being a double
silicate of potash and lime. The glass Made in England con-
tains iron or lead and is melted at a low heat. The lead is used
to give the glass a lustrous appearance as well as to enable the
workmen to cut it more easily. By means of boric acid we
may etch engravings on glass, indeed some attempts were made
to take impiessions from it as from a copperplate, but the glass
was so liable to be broken that the thing was abandoned.
Phosphorus is a substance almost peculiar to the animal
kingition. There are not in nature more than half a dozen
Wine cabs containing phosphorus, and therefore we must look
upon it as being an agent of the animal. kingdom. Vie meet
with phosphorus in different parts of the animal economy, es-
P.eci in two, namely, the softest and the hardest of all the
tissues. We find it iu the brain as well as in the bones. But
although all the brain contains it. the outside of the brain con-
tains it in the greater abundance, and some natural philosophers
consider that the energy of the mind depends upon the amount
of phosphorus which this portion of the urain contains. In w-
ilco to obtain phosphorus a simple- process is necessary, we have
recourse to the bones in which phosphorusls combined with oxy-
gen in the.tbrin of phosphoric ;teal. There are in nature two ex:
Lenitive tribes tsf animals, which are characterised by the
oi•gauization of their skeletons. One of these classes have the
skeleton in the inside and the other has them on the outside.
Those animals, such as the c rab, lobster, Sz.c., which have their
skeletons on the outside, have no phosphorus, but it exists in
those which have internal skeletons. If we take a bone and
burn,ir, there remains a whitish substance which is phosphoric
acid united with limos. If We add to this phosphate of lime some,
sulphuric acid, a great quantity of phosphoric acid is set free,
this being mixed with charcoal and heated, phosphorus distils
over. • Care must be taken in making this experiment, as there
is considerable danger, shonid the retort bleak. Phosphorus
unites with oxyg'en in several P Oportions. When it is burned
with a brilliant flame in atmospheric air, there is formed phos-
phoric acid. . If, however, we limit the,supply of oxyaeu, and
provide ap excess-of phosphorus, we shall lind.our acid to he
formed containing less oxygen. The composition of oxide of
phosphorus is not perfectly known, because it is difficult to gm
it free tenons excess of phosphorus. If some phosphorus be placed
.at the foothill of a glass containing. hot water, it will melt, and
if a Stream if oxygen. be urged upon it whilst it retnaius at the
bottorii of the vessel;- by- rneaqs of a fine Tube, irwiii• inflame
with considerable energy of combustion. A brick-red powder