Keowee courier. [volume] (Pickens Court House, S.C.) 1849-current, 1880-06-24
"SccEng by TclegraPQa.n

The latest of tho many scientific toys
which have Que after another become scien.
tiiic Instruments of moro or less practical
utility is what may be cullcd Justly
enough an electric telescope. 1t has long
been possible to write by electricity; speak.
ing by electricity has become common
enough in the last year or two; aud it is
natural that inquiring and inventive minds
should ask themselves whether they cannot
enable US to SEQ by electricity. AS usually
happens, it would seem that several such
minds have been employed upon the same
problem. An instrument for the purpose
has been described in a paper rcad before
the Cambridge Philosophical Society by
Mr.. II. Middleton, graduate of tho
Charleston College, and son of Mr. VII.
llams Middleton, of this city. Young Nlr.
Middleton, who is now completing his sol
cn,lio course in Cambridge University, ex-
plains the principle of his invention in the
following interesting letter which We liud iu
the London 7fmrS:
10 The Ettitor Of tic Times: SIR-As
! described an Instrument for this purpose
in paper read before the Cambridge Phi
losophical Society on the 9Th ult, beg that
you will publish this short account, which
processes to give solution Of tho prob
lem.
Construction of an electrical telescope
a lens is used to throw on plane or suita-
bly, curved receiving plate (encoscd in O
camcra) the image of any object. The
receiving plate of the camera is composed
of thcrmopile elements, ground to smooth
surface, and having their postoror faces
put in electrical communication by sys-
tenn OF wires with somewhat similarly
constructed plato. The heating, &c effect
OF the image TN tho first plato generates
currents of electricity, which flow through
the wire - stem, aud on reaching tho sec
ond thcrmopile plate arc rccouTcrtcd into
heat, &c., according to the law discovered
by Pcltier, tho amounts of heat, &c., being
directly proportional to tho amount Of
electricity.
Moreover, according TO the manner in
which the clements of the plates arc cr-
ranged with respect to each other, we can
get "positivo" or "ncgativo" (to use tho
crdilary phrascology Of photography, pic.
ture on the second receiving plate, since
the Pcllier effect hero holds, and tho copy
os picture depends solely OH establishing
a constant ratio in the radiant heat end
lgh. which corresponding points OF the
picture and copy send to the cyo.
Furthermore, these images can be either
viewed directly or by reflected light latter
the fashion Of the Japanese mirrors and
projection on screcn,) or by suitable ap-
paratus they can be retained as photo
graph, thcrmograph, or chemcograph,
the details of which will bo found in the
paper alluded to, and of which On abstract
will, L believe, soon appear in tho proceed
ings of the Cambridge Philosophical Co.
oiety. Also, | touched upon the method of
attacking the problem Of photographng in
colors, and in conclusion pointed OUT a
striking analogy between the camera of the
instrument and that of tho human eve; the
thcrmoelectrio clements of the instrument
and the rods and cones of the eve: the
conducting system of insulated wires en,o.
mating from the plato of the instrument
and the optic nerve Cor bundle of conduct
ing fbres OF the eye)-supposing that as
the electric currents in the instruments |
effected registration on the sensitive pa
per, so in the eye the nerve currents Of the
optic nerve probably leave some brain traoo
on the mind. | remain, sir, yours, &C.,
II. MIDDLETON.
st. Johns College, Cambridge, April22
writer in tho Scotsman AYERS that out
Of $4,000 bans imported into Hamburg
loGt C1T tyo~o CopnJ 70 oonto;, -;