New-York tribune. [volume] (New-York [N.Y.]) 1841-1842, 1841-12-22
TIL q rRIBU N E.
DR. Lardncf's First Lecture.
Second Series

foray adopted in the whole course of my pubic
teaching. There IS nothing which in itself is more
interesting than the habi, of following the steps BY
which discoyerers themselves have produced their
great results; and there is no way in which scien
tfo knowledge may he rendered more interesting
than that by which it was originally acquired. l
.halii in, bringing before you the magnificent dis
coyeries which have been rna6e almost in own
lime follow the course the discoveries them
selves have taken But in order to conduct this
inquiry with profit and interest. it is necessary
t. put you in possession Of the chief natural laws
which the Investigations of the last hundred years
have developed II may be done in brief com
pass, though, truth 10 say, they were acquired
only by and surprising deal Of
labor
Elaborate and careful Investigations has brought
10 light certain physical facts of ar extraordnar,
nature concerning Electricity. 1t mas been found
that all bodies in their natural s'ate, that state in
which We commonly see them, are pervaded through
their inmost Dimensions by TWO extremely subtle
fluids called by the common name of ELECTRICITY
but differing IN certain respects Philosopher,
generally agree to call them posture oad negotice
Eectrcities. How these two extremely a,tenuated
fluids, so attenua,ed that no means have ever yet
been able TO detect in them the quality Of gravia
ton, pervade ell substances. When bodies are in
their natural state these two fluids are contaiaed
ineq9a proportions; any body--a table, chair, &c.
contains equal quantity of the positive and ne
galive clec,rcirics. These two fluids have pro
perry OF mutual atracton-esch mOiecuie, or par
tcle of the conlescng with each particle of the
other, so as satisfy their reciprocal forces-the
compound beng found 10 produce no effect. A
body continuing an equal quantity Of these is in
stale of Electrical repose. Bu, if any external
cause disturbs tins equilibrium, breaks the union
OF tccsc TWO il.ds and separates the one from the
other, then their mutual attractive force is no longer
stsfrd and the fund becomes an active agent
the body thus disturbed possessing the and 70.
the other The body Is IN common language then
said 10 be electrified have thus briefly given |
you the u.tirn tie conclusions which have been
reached concerning this agent, and you can put
yourselves ia the situation OF philosophers with re-
gard 70 ii, since you possess all the knowledge CON
cernng it that has yet been untolded
There are various ways in which body may bo
electuted-u which the natural combination OF
thc fluids may be destroyed One of the most Com
mon is by attrition. IL TWO substances, as NV"
leaves Of paper, glass and silk, be rubbed tose-
Their the process calls into action certain Cause
which decom9oses the combination OF the Two iiH-
ids The positive withdraws from the negative,
which Is attached to the handkerchief, while the
poslye adheres to the glass. The disturbance IN
,yres a separation and neither fluid remains in It's
natural state Granting this fact, you may ask
wins is tins effect produced WHAT is there IN the
character or nature Of silk or lass winch should
cause this result To this can only say that you
know rs much about it the most prstound phi
losopher. Nothing more than the naked fact Is
known aud no principle OF " elce has been DISCO
vcred which Will explain ii. The only difference
between philosophers aud yourselves Is, that the!
NAV know greater number OF cases, but they have
no more 8 neral positive knowledge
Thus We have Is starting poiat these facts, that
there are Two fluids oi atenualed, volatile, so
spirtua! character, that tn, have M weight, nor
can they be perceived in any way but by their Ell
ttcis 1t is N,ccs.alY next to hN IN your mind
thai these two fluids, like light and heat, have
Greater facility of moving certain bodies than
over others: for example, the metals transmit heat
f.eslv while glass conducts II not ut all. Oae OF
the first things 10 be kno is the class OF substau
&c, mos, ca a lie ofcoaductins electricity and that
CLASS which does do il all, Il: Mt least but I'M
per:ectlv The bodies along which II moves with
ma, facility are the metalS--all ST them. without
exception. Ii ySu put an electrified body at enc
end OF "A metallic rod the fluid will rush TO the
othes with infinite rapidlty and will be stopped III
ito career only los meeting same non-coNdrctor.-
Tn, bodies wnIch refuse conduct the fluid can
hard be designated by any general appreciation
bat ~ may be gaid that G6r0uS bodies sucn as
worl feathers e.. noh-conductors he
hbr.s of wood are bad conductors. while wood IL
self may be good one; bur in this case the tiuid
Is CARED along by the moisture Ia lis pores LII
quds. although conductors are not very good ones
mot equal 10y any means 10 the metals 10 TINS
distinction Of bodies iato conductors and non-con
ductors | shall have occasion frequently TO refer
and 1t may be necessary 10 say that no bodies ARE
absolute aad perfect in this respect. ne conduct
ing power Is Electricity what transparency IL 10
Ii. n Glass Is a conductor OF gh,, although I'M
perfect, wnilc wood is a nou-conductor.
have mentioned, then, two main facts; that al
bodies naturally have two electric tiuds IN a state
II comb,naton. and that beng electrified consists
IN disturbing thus equlliorium and that there are
Two classes of bodies, one capable OF conduciisg
;his nd, aud the other not. The third point |
muYl notice before proceeding trace the progress
of discoveries ELECTRICITY, Is this. have
ted that GttriftOn decomposes the combined cleo
uicties. lhe same effect may be produced by
change Of temperature and IN various other ways
bu. by one in particular, which merits II
body in Its natural state-say lump of metal
be brought near an Slectrifed body, the proximity
of the latter will dccompose the eectricities OF The
former Soppo,e the body be electrified positive
"; the attraction of the positive electricity Will
draw he negative of the body in its natural state
TOWARD the side nearest Itself, and repe the posi-
tiye to the opposite extremity By this attraction
u oae and repulsion Of the other, the e!ectrcnes