Evening star., 1901-07-18
AUSTRALIAN LIGHTHOUSES.
The Remarkable Powers of the New
Macqu8rfe Light.
From the Coast Seamen's Journal


Although the greater portion Of the Aus
tralian coast is remarkably free from dam
gers to navigation, lighthouses have been
erected at every available point; hence the
comparatively limited number of shipping
disasters other than those occasioned by
stormy weather. The whole of the New
South Wales coast is efficiently lighted, and
when the service passes into the hands or
the federal government further Improve
ments will be effected. Some of the lights
are visible at distance of twelve miles.
The most important of the New South
Wales lighthouses is the Macquarie, at the
entrance to Port Jackson (SydneyD, and
which ranks as one of the largest and finest
in the world. 1t is also the grandest exam
pie of electric lighting of which the south
ern hemisphere can boast. The structure
was commenced on March 1, 1880, and the
light in connection with 1t brought into
operation June /, 1883. The old lighthouse,
which the new one has replaced, was built
in 1916, and was the first structure of the
kind in Australasia,
1t is equally interesting, and also Illus
trative of the enterprise of the state, that
the electric light was the first used for
lighthouse purposes. The light is 3f the
first order, siXteen-sided, dioptric holo-
photal revolving white light of the system
of Fresnell, showing a flash of eight sec
onds in every minute, and having range
of twenty-five miles seaward. 1t is, how
ever, discernible for considerably greater
in the atmosphere by the electric beam be-
fore the direct rays become visible. 1t vas
constructed by Chance Brothers & Co. of
Birmingham. England, under the super
vision of Mr.. James n. Douglas, engineer to
the Trinity board, London.
From that gentleman'S report of his final
inspection of the apparatus, together With
a descriptive account by DR.. Hopkinson,
one of the partners of the above firm, the
following extracts are taken: After eX-
planning that the work had been much pro-
longed beyond the intended date, owing to
unavoidable difficulties and delays which had
occurred in the casting of the various parts
of the novel and special optical apparatus,
Mr.. Douglas goes on to state that the
whole work has been completed, both as re-
CARDS material and workmanship perfect
ly. l can confidently state that the
MacQuAre light is at the present moment
the most efficient in the world Also, that
he had invented an Improvement In oil
and gas burners, by which greater con-
densation of the focal light is effected than
hitherto which he had placed at the dis
posal of Messrs. Chance Brothers for the
Macquarie light, free OF royalty, and con-
sequently the gas and oil burners for use
during clear weather have, with flames of
11a-inch diameter, an intensity of about 2J0
candles instead of so candles with the same
diameter with the old type of burner
originally intended. When these flames are
at the focus there is consumption with
the sixteen-candle gas of about forty cubic
feet per hour, and with good paraffine of
mean intensity of the flashes from the ap-
paratus at about 10000 candles, or about
five times the intensity of the flashes of the
existing Macquarie light With full power
of the electric light at the focus. the mean
intensity of the flashes in the direction of
the sea horizon is not less than 100000 or
5000 600 candles.
by a simple arrangement the charge
from gaslight to electric light at the focus,
or the reverse can be effected in ten sec
onds, and the flames of the oil lamp can be
substituted for the gas or electric light in
nearly the same space of time The Mac
quarie lighthouse is intended only to illu-
mine half the horizon; it is. therefore, pos
sfble to make use Of the landward rays by
means Of dioptric mirror. This was prob
ably the first instance of the use of a
dioptric mirror for an electric light. Spe-
cial adjustment was needed to attain the
result in satisfactory manner. The whole
apparatus Is carried on round pedestal
which offers the great advantage Of en-
abling the keeper to enter without inter-
fering with the rotation of the apparatus
Arrangements are made to burn either gas
or paraffine OIL or to exhibit the electric
light at full power or half power. When
the electric light is in use there is always a
second lamp in readiness for action The
practical result of the lighthouse has been
to make the entrance to Sydney harbor
perfectly safe, except during the most vio-
lent weather.