The Express.
London, England, 1858-01-04 00:00:00

PROFESSOR P4E4D4FB LECTURES AT 2EE

ROYAL INSTITUTION.

On Saturday Profemor Faraday delivered the third
lecture of his course on electricity at the Royal Institution.

Among the company present were M. is Dna d'Auoisle,
M. le Prince de Condi, K. le Comte de Paris, M. le Due de
Chartres, with M. Is Dottier de Massy, the physician of the
Orleans family; Sir Benjamin Brodie, Bart., ; Sir
C. Fellows, F.S.A. ; the Rev. Dr. Whewell, F.R.S.,

Him Royal Highness the Prince of Wales (attended by
Mr. F. W. Gibbs, Dr. Becker, and Lieut.• Colonel Cavendish)
took the chair at three o'clock.

The conduction of electricity, with the application of that
property to the protection of buildings from lightning,
were the branches of the subject to which the
lecture was devoted. Before illustrating the power
which different bodies possess of conducting elec-
tricity, Professor Faraday performed some experiments,
to show the varied powers of bodies in the conduction of
beat. For this purpose he employed three small cylinders
of exactly the same awn one of them being made of wood,
another of iron, and the third of copper, on the top of each
of which was placed a piece of phosphorus, and they were
all then put upon the top of a vessel containing hot water.
The relative conducting powers of the different substances
wee manifested by the time occupied in the conduction of the
heat through them to influence the phosphorus. The phos-
phorus on the top of the copper cylinder was first set on fire,
next that on the iron' whilst the phosphorus upon the top
of the wood remained unaffected by the heat. The property
of conduction, which ia thus slowly manifested by
heat, is instantaneous in the conduction of elec-
tricity ; and for the purpose of proving the diffe-
rent powers of conducting electricity which various
bodies possess, Professor Faraday connected en insulated
brass cylinder to which a charge of electricity was communi-
cated with the electrometer, first with a fins wire thread, and
afterwards with silk. In the first instance, the gold leaves
of the instrument instantly diverged; but, when the silk
was used as a connexion, the electrometer gave no indica-
tion of electricity. This important feet of the differing
powers of bodiesio conducting electricity, thoughit is essen-
tial to the production of electrical phenomena, remained un-
known for ages after the properties of electricity had been
studied. The manifestation of electricity, indeed, entirely
depends on the imperfect conduction of electric.; and, to
prove that even tho metals may be converted into
electric. when insulated, Professor Faraday placed a
bran tube on a stick of pan percha, and then,
taking hold of the projection gutta perch., he rubbed
the metal with flannel, and thus excited electricity
se readily as if it had been a tube of glass. Though
electricity passes slmost instantaneously
_through seve-
ral hundred miles of wire, it nevathelese meets with
great resistance to its transmission even through the best
conductors. Of this anomalous fact an exemplification was
given by sending the charge of a Leyden jar through a thin
wire suspended to the ceiling of the lecture room, the two
Inds of which were at one point of the circuit brought about
the eighth of an inch apart from each other. When the
charge of a Leyden jar wee sent through the wire, part of the
chargepaseedacross the interveningerap, the resistance offered
by the wire having been greater than that of the small space
of air, which is a good insulator. Professor Faraday per-
formed an experiment illustrative of the insulating properties
of carpets and oil-cloths, which may serve am a useful lesson
to experimenters in electricity, showing how desirable it is to
have a pod connexion with the earth. When standing on
the ell-cloth of the lecture-room floor, and with one band
in connexion with the electrical machine, sparks were
emitted from the other hand of sufficient power to enable
to ignite with his finger a jet of gam. On making connexion
from his body to the gas pipes of the institution, so
ma to establish good connexion with the earth, no indica-
tions of electricity were perceptible. This experiment also
illustrated the importance of making • perfect connexion be-
tween lightning conductors and the earth, and Professor
Faraday mentioned an instance of the effects of the want of
izrk:ttention to this rule, which occurred at Eddystone
use. The building was struck with lightning, and,
protected with • lightning conductor, some damage
rul4Pons to the lantern and other parts, in consequence, as
was afterwards aeoertained, of the chain attained to the end
of the conducting rod not having bean long enough to reach
the water at low tide. The concluding experiment proved
also that there Is danger in bringing conducting bodies that
are connected with the earth into proximity to lightning con-
ductors. One end of • win that traversed along the floor of
the lecture-room was brought near the conductor of the elec-
trical machine, and, when powerful sparks were sent through
it, smaller sparks were obtained on applying a conductor
close to any part of the wire, and in this manner • jet of gas
was ein on fire.

Messrs. Crossley, of Halifax, are just completing
• new chimney In connexion with their works at Dean
Clough, which will be of extraordinary dimensions and
welabt, and will outstrip every other that has ever been
built, even in Lancashire. Although placed In a valley it
has attained a level with the summit of Beacon Hill. Its
height is 127 yards, the width at the bottom being ten yards.
The weight of brick and stone need In Use erection is esti-
mated at 9,68.5 tons.— Tits Beam
BOXES OP CLOTHING IN INDTA.—Nolice has been
received of the safe and opportune arrival of the first box of
linen sent front this place to Calcutta, by the following letter
from Lady Canning to the Bishop of Salisbury, which we have
permisaion to tweet for the information of the many contd.
baton to the box —`. My lord, I have received from Lord Can-
ning your manage reepectin the box ofclothing from Slis-
bury gives to the 'utterer' frog m the di csturbances this coaun-
try. I hopem will samara the generous oontributors to
this useful • that it is most gratefully appreciated, and that
they have sincere thanks of those who ere employed in
attempting to relieve these distressed permits. I think it
will give to them to know that this gift arrived very
; for it was st once sent zip in a steamer to Alla-
WWII 40020 other gifts of clothing, to be in readiness
for the women end children from Lnctaow, when they are
delivered tram their long and terrible siege. We trust it
will please Chid that they may be brought out in safety in a
very short time. I ought to have mentioned that the clothing
was handed over by me to this committee of ladies who have
the charge of the house of neap and the distribution of
clothing. I ma, my lord, your ford•hip's obedient servant.
C. Camillus. Government Haw, Wont* Nov. 17,1867."
Jeavvra.
IPSWICH GRAMMAR SCHOOL.—It will be remem-
bered that the newt elevation of the Bev. Dr. Rimed to
the biabojirio of Antigua, rendered Tsang the heed master-
ship of Mason Elisabeth's Grammar School at Ipswich. The
rithmt is vested is the Town Council of Ipswich, and
a
body
have selected, out of 22 candidates for the meantales,
ales, the Rev. H. A. holden, sow vice-principal of Chelten-
ham College. The eapaades have alio voted a highly
complimestary oddness to Dr. Mimi on his retirement, and
the potions of the school have presented the rev. gentleman
with en epergne of the value of 160 vainest.
&CIRO HARMONIC SOCIETY, METER-HA LL.—
Haydn's IS to be perfonned ea Friday next, Bth
Julian when Mr. Sim ROM, makes hie first appeamaas
this mesea, together with Mfrs Louisa Vinning and Mr.
Nestley.