The Albany register. [volume] (Albany, Or.) 1868-18??, 1880-10-01
Tne --latest marvel OF science.


light; that is the latest marvellous achieve
ment of the inventor of the telephone.
Professor A. Graham Bell, first announc-
ed to the world in his lecture before the
American Association for the Advance
ment of Science last Friday evening.
which his discovery was made, OF the
successive experiments which led to the
final result, is a remarkably interesting
piece CT reading. The starting point of
these experiments, conducted Jointly by
Professor Bell and his friend, Sumner
| Taintor of Watcrtown, was the investiga-
| tion into the Characteristics of selenium,
an elementary substance Which las been
| known for the last sixty years, but which
has always been considered simply as
| chemical curiosity. The effect of light in
| the production of a change of its electrical
/ conductivity was discovered by Mr.. May.
the assistant of Willoughby Smith, in the
| course of some experiments looking to-
ward its Use, ca account of its high resist
ance in crystalline form TO the passage of
electricity. at the shore end of a submarine
! j.
and testing. The announcement of these
results was at first received with some in
credulity by scientific men. This curious
property of selenium has led to its employ
uent in various experiments looking to-
ward the transmission of light and its
effects by electricity. and several state
ments of the attainment of certain de-
!
made in scientific publications. Professor
Bell and Mr.. Taintor have already spoken,
by means of the new invention. which has
bee .tiristened the photophone. between
poi.-k 2l3 meters apart. The necessary
privacy of the experiments has hitherto
prevented the determining of the extreme
distance at which this new method of
communicating by speech viii be made
available, but Professor Bell finds no rea-
son to doubt that the results will be obtain
ell at whatever distance
BEAM OF LIGHT
Can he flashed from one observatory to
another. One OF the most recent expert
ments was between the top of the Frank
lin schoo!-house on Washington street TO
one of his laboratory windows on L street.
the distance being as above mentioned.
Professor Bell heard distinctly the words
"Mr. Bell. if you hear what [ say, come
to the window and wave your hat
About fifty forms of apparatus have been
devised, but to all of them the priacipIe
is common, varying the beam of light
| Just as the curreet of electricity in the
telephone is varied III intensity by the
vibrations of the voice. This beam of
light acts upon the selenium in the reneiv-
ing apparatus, Professor Bell having dis
covered that light had the effect of pro-
ducing sound in selenium. and that this
property could be utilized by placing that
substance in connection with the telephone.
The simplest apparatus yet devised con-
siSts of plain mirror of flexible material,
such as silvered mica or microscope glass.
The speakers voice is directed against the
back of this mirror, Just as it is against the
diaphragm OF the telephone, and the light
reflected from it thus thrown into CORE
spending vibrations. Any powerful
source of light may be used, but between
distant points sunlight has chiefly been
experimental with. The beam is received
at distant station upon parabolic re
flec.or, in the focus of which is placed s
sensitive selepium cell. The light may bt
controlled in many ways, and steady
beam may be modified at any point in it
path. In laboratory experiments it ha
been found that artieulate speech can b.
reproduced even by the light of kerosen
lamp. Many curious facts have beel
brought to light. For instance. musica
tones are produced at the receiver whe
no sound is made at the transmitter. !
silent motion thus produces sound. Th
beam can be entirely cut off by sligt
motion of the hand; and at the distan
receiving station musical signals, like th
dots and dashes of the Morse alphabet
can thus be produced. Another discover
is, that an effect of light passes through
certain Opaque substances. A sheet O
hard rubber was held about twelve fee
away from the receiver, but an invisibl
beam passed through, producing a f,in
: but perfectly perceptible musical tone a
the telephone connected with the selenium
FURTHER EXPERIMENTS
Showed that this peculiar sensitiveness t
vibrations of light belongs not only to Sc
= lenium. but is general property of al
matter. Distinct musical notes have beei
heard from hard rubber and many othe
: substances, while beam of intermitten
light was focused upon them by lens
and this without the aid of telephone o
a battery, aud Professor Bell says: 20
the whole, we feel warranted in announ6
ing as our conclusion that sounds can b
produced by the action of a variable iigl
= from substances of all kinds, when In til
form of thin diaphragms.' It is believe
that all varieties of articuatc speech en-
: thus be obtained from other substance.
. as win as from seIenium The simpl
way IN which Professor Bell tells how on
experiment and discovery led to anoths
= is a beautiful illustration of the lnethos
by which science guides her devote,
along the pathway to great results. Pr
Is fessor Bell entered into no specnIations ,