Oxford Democrat. [volume] (Paris, Me.) 1833-1933, 1894-02-13

A CURIOUS PHENOMENON xow.nrISo IN
vEsrioArED nv rnE LIGHTHOUSE
BOARD.

There IL = phenomenon hitherto unex-
plslnesi, which the government light
house board IL most anxious Ia elucldate.
10 relates Ia the sound-czrrying power
of fog signals, the efficacy of which IL
obviously of the utmost Importance for
the preservation of lives aud ships along
the coast. The moot powerful Kind Of
slgnal IL the steam siren which has q
metal trumpet for mouth aud boiler
like n locomotive for lungs, the place Of
vocal chords being supplied by revolv-
Ing toothcd wheel, which Interrupts the
passage ola JET of steam through the
throat of the apparatus. thus producing
the frightfui shrek that rises FROM note
to note III the scale ne the wheel goes
faster.
IL IL the most penetrating sound
known and can be- heard In calm wealth.
er at q distance ~ forty miles. Never
theless while audible at that distance, IL
Il sometimes insudlble only three or
four miles away. AZ the same moment
Of time Il may be heard distinctly at ten
miles, inaudible sgain nj fifteen miles,
aud once more audible at twenty-five
miles. The phenomenon has been fsmIl-
lar to observers for many years. Prof.
Henry during hls lifetime tried Ia In
vestigate IL aud reached the conclusion
that IL VAS due Ia q refrsction Of sound
waves caused by the Wind. One odd
thing shout II IL that the believing of
the instrument can occasionally be
heard from the masthesd of q vessel at
the same time that IL IL wholly inaudiblc
from the deck.
t'rof. ilenry's theory vas not correct.
n Il were right the phenomenon would
vary With the winds. Sometimes the
sound would be- audible al a given dis
tancc from the Fog signal, aud al other
times not, according ss the breeres hsp-
pened Ia blow. hut such IL not the case.
The area. 10 audihlllty aud insudlbllity
r,mAin the same constantly. The puzzle
I. no nearer TO solution than when u
| first excited attention.
Mr.. II. y. johnson, secretary al the
lighthouse board, has already devoted q
good deal IL study Ia this .abjcct. lie
Il determined Ia get ~ the bottom 81 ".
With that end In View he has left Wash.
ington Ia company With Prof. iIaSen of
~, weather bureau, their destination
belng Little Guli Island, OF the coast III
Rhode Island. They have taken with
them q balloon, In which they propose
Ia make .erie. ~ s.Ccn.ions within
the range % the fog signal In that local
ity.
Thus far the belt. of audlblllty aud
Insudlblllty have only been explored
aud mapped out horlSontally-th,t Ia Ia
.sy on the suffsc. ~ the water. Prof.
Harm aud Mr.. johnson propose Ia sur.
ycy them vertically.
The height az the "cone" 81 sound, a..
well a. it, length aud breadth. having
In TIL. wise b.cn determined, II will h.
possible Ia make section diagram % IL,
az several. Thu. a step viii De- taken
toward discovering the philosophy 81
the phenomenon.
Tie Importance 81 this matter \.
readily understood. Ia time 81 fog ths
mariner dsvsnd. ou the fog signal az ~
doe. on lighthous. Ia clear weather
II Ia happen. 10 ct Into belt 10 ln'
Audlhllliy near Ia dangerous coast, Ia
I. lulled Into fal.r sense 81 security, ~
depending ON the siren Tor his bearings
b. does not know where be u. Undei
such condition. the u.efuines. 10 the
signal l. most fatally impaired.
The balloon Ia b. u.-,i by Prof. IIstsu
aud Mr.. johnson in the experiment. ~
fcfrcd a. I. the same that vss employ
~ by I'rof. Harm. II sas lnhate'l
With hydrogen, holilng p.OOO cubic let
~ the ga. It, llftlng capacity ss'
sufficient Ia lift the two ob..ryer. and
sixty pounds ~ ballast. They de.lr-''
a. ascertain ih. condition IL the stmo..
phcr-, preliminary Ia som" rain msklne
trials. 4 level ~ ., IoD feet sl'o,c III,
earth ~. attained. Probably no bel
loon 10 80 small . lire ever made 81 high
VOYAGE With such load.
Prof. llagen says: II am perfect,
satisfied that the balloon !. To b. the
salvation 81 msteorology ln the ncsI
future. II Nill emanclpate "a fr"m the
ihrsldom IL theory and speculation
which has been 80 serious 4 drawback
la the past"