The Sun.
London, England, 1846-11-25 00:00:00

POLYTECHNIC INSTITUTION.

Schonbein's powder cotton and other explosives have
formed the subject of Dr. Ryan's lecture this week. The
Doctor, first of all, explained that all explosives might
be classed under four heads. First, those whose power
depended merely on sudden expansion, as steam of high
pressure—liquid carbonic acid and compressed air.
Secondly, those whose power depends upon the sudden
separation of elements which had been held together by a
very feeble affinity, such as iodide of nitrogen and chloride
of nitrogen. The latter compound, the Doctor explained,
was composed of two elements, which in their separate
condition were gaseous, but under the influence of che-
mical attraction became liquid. The moment, however,
that the affinity is overcome an explosion occurs, owing
to the return of the chlorine and nitrogen to their
original condition. Thirdly, those whose explosive
action depends upon the sudden chemical union of
certain elements which previously had only been in a
state of mere mechanical mixture, such as the explosion
of the two gases oxygen and hydrogen by the electric
spark. Fourthly, such as on ignition suffered
decomposition, and formed consequently new and
distinct compounds. To this class belongs gunpowder,
the fulminates, the carbazotes, and the powder cotton.
In speaking of the latter substance, Dr. Ryan laniented
that he was so placed as to be unable, without a breach
of confidence, to communicate the precise secret of
Schonbein's mode of preparation. Homer, he entered
into a clear statement of the peculiar action of nitric acid
upon vegetable fibre, giving numerous instances of the
observance of facts, apparently not important in them-
selves, which had evidently led to Schonbein's disco-
very. Amorg the most pleasing Of the Doctor's experi-
ments were those in which he produced explosive pre-
cipitates, by pouring into water the solution in nitric
acid of starch, cotton, linen, sawdust, &c. The pre-
cipitate from the first he showed to be xilordine
of Bracconnot and of Pelouze, and the nitramidine of
Dumas. He also showed most clearly that, although
the precipitates thrown down from cotton and linen re-
semble in its general character that produced from
starch, yet there existed some slight molecular differ-
ence, such as may exist between starch and sugar; for
the cotton precipitate was not soluble in acetic acid
while the starch precipitate was. The Doctor proposed
that, as Dumas had called the one nitramidine, the other
should be called nitrolignine. The Doctor principally
confined his experiments on the cotton to such as showed
its easy inflammability, its explosion without smoke, and
its consequent value in mining operations. On the
table we noticed the gun which had been burst in Mr.
Lancaster's hands, while firing a charge of 83 grams.
The effect on the metal was, certainly, most curious.

LAURENT'S CASINO.—This novel place of enter-
tainment, in which the amusements of the concert and
ball room are so happily blended, is now entirely
established in public favour; it is nightly crowded by a
highly respectable company, who are apparently very
e ell pleased with the entertainments presented by the
spirited proprietor, Mr. Ellis. Not a vestige of the
scientific instruments, which formerly, to so little pur-
pose, stocked the gallery, is now to be seen. The con-
cert consists usually of a dozen well selected pieces from
the compositions of Mozart, Bellini, Donizetti, Balfe,
&e. A very well arranged orchestra, under the able
direction of M. Laurent, jun., gives due effect to these
selections. The vocalists engaged are Miss Clairton,
Messrs. Binge, De Courcy, J. Roe, and the popular
Ernie singer, Mr. Sharpe, all of whom sing in a very
praiseworthy style the music allotted to them. The
dances are each evening varied, and comprise the most
popular quadrilles, polkas and waltzes; among which are
" La Peri," Musard; " The Brunnaw," Tinney; " The
Tzanmeister," Strauss, &c. Six efficient masters of the
ceremonies render the dances orderly and complete.
By a judicious arrangement the amusements cease half
an hour before midnight, by which means late hours and
consequent fatigue are avoided, to the comfort of the
visitors.
THE FIRE IN CLERRENWELL.—ADDITIONAL PAR..
TICULARS.—The fire which broke out yesterday morn-
ing upon Messrs. Palmer's candle factory, in Allen-
street, St. John-street, Clerkenwell, briefly noticed in
this journal yesterday, was attended with serious de-
struction of property. At the lowest estimate it will
reach to several thousand pounds. The factory, which
is totally destroyed, was upwards of 120 feet long by 60
or 70 feet wide. It was filled with goods, some fmished
and others partially. The firemen were unable to get
the flames entirely extinguished until nearly six o'clock.
Althoughto expdl
ai diligent e
then t
causesearchof
h theas
made,could
be nothing tend-
ing
ascer-
tained. When the factory was closed the previous night
everything appeared perfectly safe. We are given to
understand that upwards of one hundred men will be
thrown out of employment by the calamity. The follow-
ing is Mr. Braidwood's official report of the damage
done : Messrs. Palmer's factory in Allen-street, burned
down, and contents destroyed—insured in the Phoenix ;
Nos. 1,2, 3, and 4, Compton-court, let out in tenements,
front scorched and window glass demolished ; Nos. 5,
6, and 7, several squares of glass broken in buildings.
and damage to furniture by removal ; No. 61, Compton-
street, J. Holland, engineer's tool maker, back front
scorched ; No. 62, ditto ; Mr. S. Hill, watch and clock
maker, similar damage ; No. 63, ditto, like damage ;
No. 64, G. W. Young, licensed victualler, damage to
stock by removal, and some glass broken ; Messrs.
Hooper, black lead mills, roof damaged by fire and cut-
ting away—insured in the Norwich Union Office.
PROPOSED BREAKWATER AT BRIGHTON.—A pub-
lic meeting of the inhabitants of Brighton was held at
the Town-hall, on Monday, for the purpose of taking
into consideration a communication from the Brighton
Suspension Pier Company, respecting their intention to
construct a fixed breakwater at the south end of the
chain pier fur its protection, and t
fishmg
o-baoffatosr,d
asnhde
other
ships, steam-packets, yachts,
vessels, and to facilitate the embarking and_ disembarking
of passengers, goods, and merchandise. .W Catt, Esq.,
the high-constable, was called to the chair. Sir Samuel
Brown, the engineer of the Pier Company, explained
the principle of the proposed breakwater, which is to
be erectsd on the south of the pier-head, not exceeding
a quarter of a mile distance, and extending about the
same length in a crescent form east to west, which
would afford shelter for steam-packets of all classes, and
access to the pier at all times. The breakwater will be
constructed of a series of iron bars, formed into a mas-
sive framework, and well ballasted with granite blocks.
t ors ofnpe ticeht theanheidßc
advantages
lml
The section in depth was to be eighty feet, so as to break
e
completely the force of the waves. The expense was
declaredp
wanhyi havingehhi
s Now,ifli
the
be
segpna proposedo
epkspeslniteinsfuosfptrarpvunoocerutxturtrienso:fscrstaiahoprnel,
estimated at 15,0001. Sir C. Malcolm and other direc-
pharainimlicePi
authorising the completion of the plan. The meeting
morning last the early railway train
theonosepFariradtaecyl.
with anda killedmouse, a finea
hb be
at
cwke en
cat,l iwe nde ahl awnads Le
raons es
iaus tge
rthreanlinoveer
was too intent upon her prey to notice the approach of
the engine. The cat was afterwards found completely
fixed cut in two, with the mouse firmly between her
teeth.—Carlisle
nETlTiox o
Patriot.r
rEsN
A PURSE TO THE PRINCE OF
WALES.—Mrs. Fead, the lady of Colonel Fead, C. 8.,
late of the Grenadier Guards, who resides near Black-
heath, presented his Royal Highness the Prince of
Wales, on his birthday, with a most magnificent and
unique purse, worked with her own hands. Her Majesty
has most graciously acknowledged the present, and con-
descended, in the name of the Prince, to accept the same,