Memphis daily appeal. [volume] (Memphis, Tenn.) 1847-1886, 1879-04-06
TYNDALLS

Last Lecture on sOund-Very Interest
ing OBSERVATION-DISCLOSURES Vibrations
The Anatomy OF the Ear-PuI-
| satfCns as Physical SEN
London Times, February 2lst: "Prof.
| Tyndall began on the thirteenth instant, at
| the Royal institution, a course of lectures on
sound. EXPERIMENTS were numerous; fer, as
the professor stated, he aimed rather at
| showing things than telling about them.
| after briefly describing the anatomy OF the
ear and slluding to the external physical mo-
| ton of waves Or pulsatlons becoming inter-
nal physical sensations, he spoke OF the I'M
| portance of having at the outset IF the study
| Of sound a clear mental picture of sound
waves-of the raretactions and CONVERSATIONS
| of the air caused by sound vibrations. In
| illustration he had two sets of apparatus
One was 3 series of balls, united together
with coiled metal springs; the other was SIM
| liar except that The springs were stronger
| These served to illustrate two points-the
motion Of air particles passing on from one
| to anothsc an impetus given to them, AID the
| fact that the stronger the springs the more
rapidly is the effect OF that impetus conveyed.
| In the cir the elasticity or the spring, as
| Robert 3 pyle called It, influences the rate at
which sound travels. At temperature of
| thirty-two degrees Fahrenheit the air con-
veys sound one thousand and ninety feet
| per second, but every variation IN the
| temperature alters this. 1t Is well known
/ that when a mechanically striking bell is
placed under a receiver exhausted OF ar no
sound Is heard. It was shown that when a
| little air, about one-fourth, was admitted,
| sound was feeble only. Hydrogen was then
! admitted and the sound was again ex-
! tinguished. Prof. Tyndall devoted some
| time to the explanation Of this phenomenon
| The fact vas known to Sir Jonn Herschell,
| and he gave the explanation that hydrogen
| broke the continuity OF the medium; for he
| had observed what he took to be a similar
! phenomenon with champagne IN a glass. a
! glass of champagne, not fOamlng, when
| struck, will give out the clear ring proper 10
| the glass. but when more champagne IS
poured IN and there is a foaming disturbance
there Is no ring. The professor illustrated
| this with a large Jar, using carbonate of soda
and tartarlc acid. THIS, however, Is not the
explanation. Prof. Stokes, paying attention
to the fact that when a tuning-fork Is struck
and held In air 1t gives out but little sound,
studied why this was. He arrived at the
conclusion that AIR Is so mobile that IL runs
round the tuning -fork without being thrown
into waves. The running round may be
checked by holding a card at one side Of the
fork, and at once the sound Is augmented.
Hydrogen Is still more mobile than air, so
that the probable explanation of the bell not
sounding IN it IS that the hydrogen runs
round so readily that 1t is not thrown into
soGnd-signas is the effect of wind on sound
Many observers have come to the conclusion
that sound Is often heard better across the
wind than with it. Here, again, Prof.
Stokes studies were referred to. He gives
the explanation that there occurs something
analogous to the reiraction of light. Wind
1t Is we'll known, is retarded by friction In its
passage over land surfaces. la the higher
regions 1t moves more rapidly. The sound
waves probably behave as hght-waves do in
passing from one medium into a denser,
where they are retarded. In striking OBJ
hquely retardation commences more rapidly
IN one part than another, and refraction fol-
lows. Near the earth the motion of wind ie
slow compared with the upper strata; prac-
tlcally, sound ttiAg the wind strikes It OBJ
lquely, so that 1t Is refracted from the course
1t would take, and that IN an uo-
ward direction away from people stand
Ing on the level. Abiding 20 Newton 5 at
tempt to reconcile his theoretical calculation
of nine hundred and sixteen feet per second,
with the experimental results of one thousand
and ninety feet per second as the rate of mo-
ton OF sound, Prof. Tyndall mentioned he
had forgotten TO take into account the warmth
developed by the sound wave in its own
path. Ide audience was shown with q Their
moplle aud geivaoOmcter arrangement that
very gentle and small compression of air
oic produce heat 4 number OF experiments
OF the passage OF sound through wood, water,
etc, were made IN tie concluding part of the
lecture, and there was repeated the inter
eating experiment CT music played IN the
cellars OF tEe IlSLtlt beng made audible
by C5uuecting wooden rod rising into the
theater, on which a common wooden tray
was alternately held and removed TIE rod
itself has not surface enough 10 give vibra-
lions that can be heard, but the larger sur
face of the tray gives the magic music -
sDri5g Novelties for Women.
New York EUeHing Post: The coaching
hornets this year are to be of Legborp and
Tuscan, with vide brims; the inside of these
carriage bOnnets IS merely faced with velvet
or with shlTrlugs of satin, no other face trm-
ming being ems Logged. Among the bonnets
shown are several striking styles copied from
French models and attract much notice; one
II them was OF Leghorn, with a square crown
and drawn satin facing, and outside trim
ming OF three ostrich tips, mixed with Mar
shal Neil roses; another one not quite so
large or so fiaring and more IN the direciOire
shape, with broad cape, had iaQueminot
roses and feathers. In smaller bonEets for
street wear the capote aud cottage shapes are
preferred. One OF the c1pOtes Of white CHIP
was edged with quillings of fine Breton lace,
and the crown was covered with a soft SATIN
crown piece of pale pink satin embroidered
in the directeire COloIs, of which the pale
blues, plnks and olives seemed 10 be IN per-
feet accord with the prismatic tints of several
title humming birds, which were also used
IS trimming. A black chip with the true
ef-eater crown was trimmed with a satin
cart and shaded butterfly and pale pink
oses. Several round hats exemplifed the
omlng fashions for summer. One in a he'll
net shape, with square crown. was trimmed
With tInsel braid and black satin ribbon,
ormlng scarf, through which gOld-hilted
iagger was stuck; gold aud cut steel dag
,ers, swords and long ornaments OF all kinds
re seen on round hats. A turbGn IN old
sold and garnet mixed straw, one of the
newest fashions IN straw goods, was trimmed
With grenadine scarf of the same oolors'
The winner on His VVey.
NEW YORK, April 2.-The English pedes-
ran party consisting of @. w. Atkinson of
he Sporting Life, Charles RoweIl and his
tteodants, Simpson and "Plen," took its
departure for England by the Scythian to-
ay. There was no formal leave taking and
oue of the leading sporting men OF this city
Tere In attendance to wish Rowel and the
Istley belt safe passage. Among Rowell's
lggage were conspicuous this belt In a glass
use and testimonial of the Albion and Brit
IN Provident socleties. Atkinson SAID that
lowell takes back to England about nine
zen thousand dollars as net proceeds of his
ak a; Ghmore's garden and several exhibit
Ons IN Boston, Philadelphia and Baltimore.
e had also received many mementOes of his
sit IN The form Of enGrossed testimonials,
OLD watch aud chain, valuable diamond ring
ON p lady sdmter, diamond scarf-pin, etc.
Dwell would not talk much about his future
'aquests, but said tcat the man who took
Re Ashley belt from him would have to go
long way" He expressed himself highly
ratified with the kind reception and gener-
Ia treatment he had met with from the
lblc and press, and said IL was not improb-
Die that he would come TO America again