, 1870-07-25

II, ne Et.if.r of The cA,ca5t' Tribune:
have Leen solicited by my frsen1s from
various pa1ts Of this State, to express my
op;n,on IN the merits Of the letter recently
published in your paper. purpostinG to be
from Professor Henry, OIL the subject OF
hehtuine-rods, and, With your Permission.
would BE- glad to give my reply as wide eircl'
1ation. through the columns Of your paper II
Tie letter to which they refer has had.
The letter itself ,coks 1istle smoky. for on
pase 52o, in the Patent Ollie Report for 1859
viii be found tho same INSTRUCTIONS, rertstim
ef hierati17, with the same aLtsnia that 20 ina-
movements had been made in Lightning 5-zods.
Ii this il true 1t the present titsar.
then the teaching Of philosophy in
our public schools ae all wrong. and thesa
nbysic1rte who have devoted the !7ss twenty
or thirty gears to experiments and lnEe1tsgA-
tiors On this subject, are Ill wrong but the
| iuetructions are inconsistent with the ~i1t1ns+
Of Professor Henry himself. As we'll ~ those
Of al modern writets With whom an &C.
| ouaiuted In letter which receiSed from
| Professor Henry in 1564. he referred tueto the
works Of Becquerelle, ~ the eest authority on
on electricity, and ind hy hiH authority that
corper has rs times the conducting power oi
i-tE. lI3 t1aes thst Of platins- and several
| million tiraes that Of water III the same let
| ter Professor Henry says, that with given
weigh, OF COPPER hollov tuhe or cylinder u
rod" Wrllt, IN his Natural Philosophy, sa!s
,ha, ..el. cstic1.y resides merely upon I'll. sur
face OF conducting bodies aaa does not leae-
trn.e any denth within
| Any one Who has expe11tnenteo R7tn eleetr1e-
i,y. knows TIA, tin foil, or guld Leaf, ril1 be
A. efficient in conducting capacity as solid
Mate Ct metal. Nov WY f2,ten An unsiShtly
lar of round i1uu an incn in diameter. upon
the house for liShtning-rod, uhen Light
corr er tube II inch in diameter, will coad1c:
more than three times Is ouch electttcitF:
| n sidee, there are numerous cases on record,
in which she ligltIing has left tue iron rot Tor
| some better conductor. In the Patent Office
Report referred to. Prof. Henry mentions
! three sucL cases, 4 d can mention two wh.e:l
which y A. on the house Of DE-. Bradley Of
Ero. head. Wis, in which the electricity te't
the rod and tore itr way 10 copper bell wire
which it followed through the honse.
No such .esidens could u happen pe;a+ WITH ~
fof there is nothing in house e3cept silraz:
which il = better conductor thtn copper, aud
not uauy dwellings contain enough silser 10
nale Them 1t al dangerous !Tof FaraasE
and o;bers recommend parting the roda on the
sS;d ,ba, Il vou would PICS coppAr ro.i
| through barrel Of EunpordeF, he no I'D ii
n The head during thunder shower. would
! not hrsitxte to do ii myself, for We know that
, god CONDUCTOR during the. discharge Of J
es,rnke Of lightning The main md ou my owr
houre is fastened 10 shs chimney md passes
. through the centre Of the house 70 the bottom
~ the cellar aud many scientific men hAyt
rrorounced it the uust seEsible arraugemeu
D ! they have ever eeen-
IEe idca Of connecting Al iron rod to tht
, building with irun hooks Is simply ridtcul ous
! when evcsr modern vrittr on this subject ssy
:: tba, The more intimately the rod ia oonnecse,
; with the building the 1,ore perfect the prosec
tion. non cntr from the direct, but from tn
a inducfiye charge In the Pztent ohce Repor.
Frof. Henr, SAYS the copper rod should b
a eolde1ed to a metallic rotf. In regard to pain,
d / inc rod. the statement Of Prof. Henry. tna
:. coating af resl;r.e wa1 was thrown OF in
e heavy discharge, would plainiJ show that az