River Falls journal. [volume] (River Falls, Pierce County, Wis.) 1872-2019, 1893-12-21
THE LARGEST LIGHTHOUSE.
On a Clear Night the Light Is Visible One
Hundred and Thirty Miles.

=
Hundred and Thirty Miles.
II there is one thing the French gov
eminent has endeavored to do well it
has been to warn mariners of danger
GUS parts on the French coast, and IL
there is a spot where the Service des
Phares de France has largely expert
mented with a view to providing the
best method of lighthouse illumination
it has been at the lighthouse at the
Cap de la Heve. near Havre. Four diff
ferent kinds of apparatus have al
ready been tested at this lighthouse.
The first comprised oil lamps with re-
Electors, giving a luminous intensity of
eight thousand candle power, visible
in clear weather distance of forty-one
miles In the second case oil lamps
were used with fixed lenticular appa-
ratus. yielding a candle power of nine
teen thousand. capable of being seen
in clear weather a dista ice of forty
nine and one-half miles. The third
comprised the employment of the cleo
trio arc light, with fixed lenticular APP
paratus, giving an illumination of
twenty-four thousand candle power,
the light being visible ffty-seven
miles away. In the fourth case the
use of the electric arc light was COM
bined with a lenticular flashing appa-
ratus, yielding twenty-four million
candle power, and capable of being
seen on a clear night no less than one
hundred and thirty miles distant
A new light has. however, now been
practically completed at this light
house and this will give a luminous
intensity of 40, 900, OOO-candle power and
it will be the most powerful lighthouse
| light in tie world AS far as the cleo
trical apparatus is concerned. the old
magnetic machines have been dispensed
with and four new generating ma
chimes have been substituted. These
are two continuous-current dynamos,
| giving each from twenty-five to 100 am
peres at pressure of seventy volts.
and two new De Meritens alternating
current magnetic machines, yielding
from twenty-five to 100 amperes at an
| electro-motive force of from forty to
forty-five volts. The current yielded
by these machines will be utilized for
producing light in Serrin regulating
lamps fitted with cylindrical carbOns.
| The optical apparatus which has re-
| placed the old fixed lights is of a new
type, devised by NJ. Bourdelles one of
| the chief engineers of the Service des
| Phares and who was a prominent
member at the recent international
maritime congress held in London.
| This apparatus gives white flashes
which succeed each other every five
| seconds, and it possesses this peculiar
ity-that the number of lenticular
panels, which in lighthouses of the first
order ranges from eight to sixteen, has
been reduced to four The difficulty
of revolving the panels at the necessary
rapidity to produce the flashes at suffi-
GENTLY regular intervals has hitherto
prevented the realization of this inn
portant improvements; but this has now
been overcome in an ingenious manner,
and il is now possible to make a COM
| plete revolution N twenty seconds, as
| compared with minimum of four min
utes with the ordinary lights of the
first order. The square lantern has
been demolished and a circular one
substituted. The new light will, as
already mentioned, be the largest light
house light in the world. During eleven
months of the year the light at the
Cap de la Heve will be visible from its
geographical bearing a distance of
twenty-three miles, while with the old
fixed lights this limit has only been
obtained for eight months in the year,
leaving out of consideration the greater
luminous intensity obtained with the
new apparatus.-Pall Mall Gazette.