Juniata sentinel and Republican. [volume] (Mifflintown, Juniata County, Pa.) 1873-1955, 1876-05-24

sCIUTIyIC.
Animal Pkosph0resceacees. -Amonl
the marvels which excite the admira
ration of the student of Nature, no
the least strange Is the group of phe
nOmena known under the name o
Animal Phosphorescence. We are 9,
accustomed to associate light with heat
and to consider that fire of some kint
is necessary to its production, that tn,
imagination is appealed to with un
usual force when we find it proceed
ding from the body of living animal
Yet, it is we'll known that the emission
of light is not an uncommon character
istic among the members of the in
vertebrate divisions of the anima
kingdom. Travellers have often expa
tiated on the beauty of the scenes
which they have witnessed in the trO
pics, when the seas or forests have
seemed to be illuminated by innumer
able sparks of fire and recent discOv
cries have shown that the luminOul
quality is even more common than wa
previously supposed. During the dred
ging expeditions of II. NJ. s. POrcupins
in the years of 1869 and 1870, SO many
of the deep sea animals were found Il
be phOsphOrescent, that Prof. Thorn
son has suggested that the light neces
sary to the development of the eye
sight which some of the specimens
possessed may have had its origin il
that source. In animal phOsphOIes
cence, as in all her works, Nature ex
hibits an immense variety in the fOrml
in which she displays her power il i
one case, the luminosity will be visible
manifest itself through the action of 9
minute and complicated organ one
species of animal will shine with q vel.
low light; a second. with brilliant
green q third, with pale lilac; and We
are acquainted with one instance in
which the light changes successively
to the chief cOlOrs of the solar spec,
trum. The causes which produce these
phenomena are still very obscure. Al
though many forms of life are known
in which the luminous quality is pre-.
sent, scientific men are not yet agreed
on what the quality depends; and the
purposes which the light serves in the
animal economy are also little under
stood. But the phenomena themselves
are often very remarkable.-POpufdr
Science Monthly.
The Electric Lighthouse at South
FOreldnd.-In the lighthouse at South
FOreland the Electric light is employed
and the electric current is generated
by means of large magnetic-electrO
machines, which are driven by betting
connected with steam-engine. Each
machine is composed of 96 helices,
mounted upon six gun-metal wheels
each of which carries is helices. Be-
tween these wheels are placed the
magnets. in each division, 40 of which
are composed of six layers or leaves r.
veted together. while the f6 end ones
have but three leaves each, The mag
nets, which are mounted in frames, are
stationary, while the helices revOlve
at the rate of 400 revolutions per min
ute. The power absorbed by the cleo
tric machine alone, including friction,
is four indicated horsepower. The
power of a magnetO-electric machine
is according to the gross attractive
power of its magnets, each magnet
having a certain lifting or attractive
power expressed in pounds. In the
machines at South FOreland each of
the slx-plate magnets will lift los
pounds, and each of the three-plate
81 pounds, making the attrac-
tive power of the magnets In one ma
chine to be 51S4 pounds. The proportion
of the lifting power to the weight of
q magnet is a good indication of its
value, and, generally speaking, mag
net which will lift two and half times
its own weight is a good one. Each
six plate magnet at South FOreland
has a weight of 43i pounds, or two
fifths of los pounds. The machines are
by underground cables with
the electric lamps placed in the lenses
Of the tower. The carbOns used in the
lamps are ten inches long by three
eighths of an inch square they are re-
and consumed at the rate of four in
,hes per night for each lamp. The
enses are about the same size as ordi-
nary third-order lenses.
Wind Measarer.- thermometer
has now been improved to such de-
gree that it not only denotes changes
IN the force and velocity of the wind,
but keeps a record of the same. In
his arrangement, the essential part is
! plate, having its face constantly pre-
,ented to the wind, by set of vanes at
right angles to it. The force of the
wind on the plate causes it to move an
arm carrying a pencil, which makes a
mark on a sheet of paper. especially
-uled for the purpose, having separate
for registering the force
md duration of the wind and third
20 show the amount of rain. The paper
S slowly moved by clockwork. The
pencil approaches or recedes from the
,dge of the paper, as the wind varies
n force, while similar pencil attach
nent to an arm, connected by a spiral
worm and nut to the guide vanes, re-
yisters the direction of the wind in the
,entre compartment. The rain gage
s attached to bent lever, also carry
ng a pencil, which is drawn towards
he centre of the paper as the gage be-
ONES filled with water, thus indica-
ing the amount of rain. When the
,age Is completely full, it tilts, empties
tself, and the record commences afresh
the operation being simple and per-
ect.
A Woonsocket (R. I.) inventor has
ately exhibited in public a patent "ro-
ary fire extinguishern of his cOntri-
IL l5 uCsCIluCu dS COuslstiuS VI
hollow brass cap, with a perforated
Ound top, placed upon an upright two
nch iron pipe, about ten feet high,
rom which extend two hollow brass
rms an inch in diameter, at right an
lies, with a slot on one side of each
rm near the end. When the water
vas turned on from the hydrant the
ap and two arms revOlved rapidly,
hrOwing from the holes in the ends
md sides a heavy, drenching spray
'ver an area of two hundred and twen-
y feet; small streams spurted up at
he same time from the top of the
prinkler, several feet high the whole
pparatus discharging sufficient water.
he inventor thinks; to instantly ex
inguish a fire i'm a large room full of
Ombustible substances, or on the roof
f large building.
A. ron WOlkenstein has recently
made some experiments on the skin of
rOgs, kittens, rabbits and mice. He
ivided the skin at the upper part of
he thigh, and then withdrew 1t over
he toes; the sac thus formed was
lied with distilled water and i'm
nersed in test solutions of various
ats. The results obtained were as
ollOws: 1. The skin Is permeable to
Tatery solutions, but not to cOncentra-
ed solutions. 9. Increased tempera-