Year: 1885

page_text: I, JOHN RICHARDSON WIGHAM of Albany House, Monkstown in the County of
Dublin, Ireland, Gas Engineer do hereby declare the nature of this invention to
be as follows:-
My invention relates to improved means for the illumination of lighthouses
whereby I am enabled to light every part of the horizon simultaneously without
requiring the lights to be revolved for this purpose, and also to improve the
character and quality of the light transmitted by lighthouses.
To effect these objects I employ the description of lenses known as "annular
lenses" which have the property of transmitting all the light which falls upon
them from an illuminant in lines parallel, or nearly so, in contradistinction to that
kind of dioptric apparatus which is intended for fixed lights and which only
parallelizes the light which falls upon it vertically from the focus, and radiates
the light which falls upon it horizontally from the focus to every part of the
horizon with equal power.
Such annular lenses I place in tiers one above the other in such a manner that
the beams of light transmitted through each of them shall overlap those proceeding
from the contiguous lenses, whereby they will transmit the light to every part of
the horizon simultaneously, thus avoiding the necessity of revolving the lenses, and
enabling them to answer every purpose of a fixed light, being continually in the
eye, but with the superior power which annular lenses have over dioptric apparatus
with fixed lights.
Each lens has a burner of any suitable known construction, whether for oil, gas,
or other illuminant, in its focus; when gas is employed for these burners, or for
those bufners particularly described in the next paragraph, this could be cut off at
given intervals so as to reduce the cost of consumption, and its illuminating power
may be increased by the employment in combination therewith of naphthaline in a
manner similar to that practised with what is known as the "Albo-Carbon Light."
I employ in combination with the above described arrangement of lenses, as also
with that described in my Patent N° 6195 of 1882, a new construction of oblong or
polygonal burners, by the use of which instead of the circular burners heretofore
employed, the power of the light is improved.

page_text: If gas be employed as the illuminant, I employ in combination with the burner,
an "oxydator," such as described in my Patent No 945 of 1865, also made of corre-
sponding oblong or polygonal form, arranging the same so as not to interpose any
obstruction to the passage of light from the burners to the lenses, and, if required,
I provide any suitable known means for intermitting the flame for the purpose both
of economising the illuminant, and at the same time giving distinct individuality
to the lighthouse where it is used.
.
In some cases, instead of employing one oblong or polygonal burner, I apply
three or more separate circular or polygonal burners' to each lens, whereby, in the
case of revolving lights, I produce three or more separate lights visible in regular
succession as the lenses and burners revolve. In this case also, when gas is tho
illuminant, means may be provided for intermitting the flame.
Dated thin 02nd day of December 1885

page_text: I, JOHN RICHARDSON WIGHAM of Albany House, Monkstown in the County of
Dublin, Ireland, Gas Engineer do hereby declare the nature of this invention and
in what manner the same is to be performed to be particularly described and
ascertained in and by the following statement :-
My invention relates to improved means for the illumination of lighthouses
whereby I am enabled by an improved method to light every part of the horizon
simultaneously without requiring the lights to be revolved for this purpose, and
also to improve the character and quality of the light transmitted by lighthouses.
To effect these objects I employ the description of lenses known as annular
lenses which have the property of transmitting all the light which falls upon them
from an illuminant in lines parallel, or nearly so, in contradistinction to that kind
of dioptric apparatus which is intended for fixed lights and which only parallelizes.
the light which falls upon it vertically from the focus, and radiates the light
which falls upon it horizontally from the focus to every part of the horizon with
equal power.
•
Such annular lenses I place in tiers one above the other in such a manner that
the beams of light transmitted through each of them shall overlap those proceeding
from the contiguous lenses, whereby they will transmit the light to every part of
the horizon simultaneously, thus avoiding the necessity of revolving the lenses, and
enabling them to answer every purpose of a fixed light, being continually in the
eye, but with the superior power which annular lenses have over dioptric apparatus
with fixed light.
Fig. 1 shews diagrammatically the overlapping of beams from a number of
annular lenses. Thus the sectors a representing the beams from the light of one
tier, the sectors b may represent those from a tier below occupying the spaces
between the sectors a. Obviously, instead of two tiers a and b, there may be a
number of tiers sending their beams in intermediate directions and so giving
uniformity of illumination all round.
Each lens has a burner of any suitable known construction, whether for oil, gas,
or other illuminant, in its focus; when gas is employed or for those burners parti-
cularly described in the next paragraph, this could be cut off at given intervals so
as to reduce the cost of consumption, and its illuminating power may be increased
by the employment in combination therewith of naphthaline in a manner similar
to that practised with what is known as the "Albo-Carbon Light."
I employ in combination with the above described arrangement of lenses, as also
with that described in my Patent N° 6195 of 1882, a new construction of oblong
or polygonal burners, by the use of which instead of the circular burners heretofore
employed, the power of the light is improved.
Fig. 2 is a diagram shewing a burner B of elongated oval or elliptical form in
connection with an annular lens L.
If gas be employed as the illuminant, I employ in combination with the burner,
an "oxydator" such as described in my Patent N° 945 of 1865, also inade of corre-
sponding oblong or polygonal form, arranging the same so as not to interpose any

page_text: obstruction to the passage of light from the burners to the lenses, and, if required,
I provide any suitable known means for intermitting the flame for the purpose both
of economising the illuminant, and at the same time giving distinct individuality
to the lighthouse where it is used.
In some cases, instead of employing an oblong or polygonal burner, I apply three
or more separate circular or polygonal burners to each lens. By the use of three or
more burners as shewn diagrammatically by Fig. 3, B B B indicating 3 circular
burners in connection with the annular lens L. In the case of revolving lights,
I produce three or more separate lights visible in regular succession as the lenses
and burners revolve. In this case also, when gas is the illuminant, means may be
provided for intermitting the flame.
Having now particularly described and ascertained the nature of my said
invention and in what manner the same is to be performed I declare that
what I claim is :-
1. For lighthouse illumination, the arrangement of lights and annular lenses in
tiers one above the other the beams from each tier being so directed that they
overlap those from the other tiers, substantially as and for the purpose set forth.
2. In combination with annular lenses for revolving lights the use of burners of
elongated form, substantially as described.
3. For revolving lights, the use of three or more circular burners, in combination
with annular lenses along with which they revolve, substantially as and for the
purpose set forth.