The daily dispatch. [volume] (Richmond [Va.]) 1850-1884, 1877-04-21

PRESENTATION, &C, &C.
A large and brilliant audience gathered
in the fine chapel OF Richmond College eve-
ming before last to hear lecture on the
telephone by Professor C. Ii. Winston, OF
the college. The lecture was made ut the
request OF the Philologian Society. After
a brief Introductory by the president OF the
Society (afr. Barglebaugh), the Professor
came forward to his desk, about which
many pieces of apparatus were gathered,
and announced his subject. He indicated
his purpose to avoid the extremes Of dry
and abstract scientific discussion Oh the one
hand, and mere display OF unconnected
and unexplained experiments Oh the other.
In the next place, he wished at once to un-
deceive any who came expecting to see the
telephone itself by recalling the exact state
ment Of his theme, which was "Some of
the Principles Involved in the Telephone"
But what is the telephone? Etymologi-
cally, it is akin to the telescope and the telc-
graph. AS the one is the far-seer and the
other the far-writer, So this is the far
sounder. In other words, the telephone is
contriYance for transmitting q sound to
distance; or, rather, for hearing at one
point sound made at another point which
may be very remote.
The Professor then went on to explain
that as tine means employed for telephone
transmission was the electric current it
would be needful, for fair appreciation OF
the subject, to discuss briefly some of the
laws both Of sound and OF electricity. Be-
ginning with sound, he announced, first,
that sound, rs an objective reality, is Yibra-
ton. He showed this clearly with some
| simple experiments on various sounding
bodies before him-as bells, glass bowls,
musical strings, membranes, tunin2-forkS,
&c. Avery beautiful experiment was made
by throwing 4 narrow beam OF light from
the oXyhydrogen lantern, which stood on
the platform during the lecture and was
well manipulated by one OF the students,
upon Il smail mirror attached TO the tongue
OF an ordinary organ-recd. When the reed
was made to sound, and the light from the
little mirror, now in rapid vibration, was
thrown upon the screen erected behind the
platform, the effect was beautiful.
But when the Professor, with word or
two OF explanation, introduced the appara-
ttls for making what are known as TiSSa-
/ ions' curves, IN which there are two minors
| vibrating in two planes At righl-an@lcS to
mirror is reflected to the Other and thence
|
May curves OF almost bcwitcliing beauty,
which called forth most enthusiastic az
plau-c. Having thus made familiar the
i:;ca that sound is vibration, the lecturer
next took up and ciucidatcd SGmc differ
cnccs hy which soand. are distinguished
from each other. With the beautiful instru-
mcnt known as the siren he Illustrated the
fact that high and low sounds differ from
each Other only in the lTi'GlE' oi the vibra-
| tionS, and that Tia. ptc:I oi any sound is
exactly characterized by stating its number
| Of vibrations per second, which number
ray be anywhere between 10 for the lowest
sound and 5000 for t:lr highest audible to
human ears.
| 4 brief consideration vas then given to
the matter vi the quality OF sounds, that
which is also called the cl0ng or the color OF
| the sound, lv which is meant all that indc-
scrbahle bit perfectly apprcciable differ
encc between 4 certain note is given by one
| instrument or one voice and exactly the
same note aS given by mother instrument
or voice. The Professor made this clear by
experiments and otherwise, and showed
khow it was Just here that the telephone was
| 10 be llit 10 the sevrrcst test. 1t might re-
produce sounds in the same key, and even
| OF tie original intensity, but coald it give
| the OfiSltl;ti cidiiN VI lOiC IHlS, IL W
claimed, BrlFs telephone had done.
The next point brought out by simple but
strikin. experiments was the capability
which sounds have OF being augmented or
magnitied by the proximity OF body capa-
bic OF making the same sound. The i'm
portance OF this feature in reference to the
telephone was easily apparent. 1t was
Illustrated by the resonance Of tubes, men,
cranes, &C.. to the notes OF tuning-forks,
whistles, horns. and even to the voice. But
the principle itself and the skill of the cX-
perimenlcr we're put 10 the highest test in
the trial OF t!e matched forks. In this ey-
pertinent two tuninS-forlIs, Opt;caily tuned
TO exactly the same note. were placed some
twenty feet apart, pains being taken that
there should be no solid connection be-
tween them: then one OF the forks was
sounded for . moment and quickly stopped,
when it was found that the other had caught
and was producing the sound.
Finally, on the subject OF sound, and as
exemplifyins most OF the principles alluded
TO, the lecturer introduced the truly bril-
! liant and almost startling experiments OF the
santi!ive flames. a thin gas flame was made
10 stand about twelve or fifteen inches high,
and at the slightest sound anywhere in the
room il would quiver and stoop, as il afraid
The rattling Of q bunch Of keys twenty feet
off would throw it into shiver, and when
the Professor held his watch near it the
flame would respond to every tick, throw
ing out pretty ruflle on the edges and rust
ling in perfect Synchronism. The audience
showed their appreciation by hearty ap-
plause.
Turning next to the means OF conveying
these sound-vibratlons to distance, the
lecturer showed, first, how impossible it
would be to conduct them direct rs in the
well-known experiment OF playing musi-
cal instrument in one room and conveying
the music by a wooden rod through one
apartment to another, where it was fully
brought out by applying soundins-board
OF some kind to the end OF the rod. No; !;
the telephone is nothing at all like the toy
known as the lovers telegraph, which con-
yeys sound directly by a stretched string.
1t is far more nearly allied to the electric
telegraph Indeed, the whole theory OF the
telephone may be briefly summed up thus
It is q contriyance, first, for the conversion
OF sound-vibrations into electrical pulsa-
tions; secondly, for the faithful and rapid
transmission Of these (Which we know is
easy for any desired distance); and thirdly,
the reconversion Of these into the original
sound-waves.
We need not follow the lecturer in his
rapid outline OF the principles involved IN
the electric telegraph, which he had in ope-
ration in the room before him. we all know
that the ordinary telegraph depends for its
action upon the single fact that by means Of
the electric current, which can be made and
broke at pleasure, we can cause one piece Of
iron to attract another and cease to attract
| 4 yk,s M 1oo9ttnr