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BLEECO Worthing (100W) / BLEECO Open Type Conical Lantern 677
Genre: Open dome refractor lantern
The open dome refractor lantern appeared in the 1920s, a result of the burgeoning scientific
approach to street lighting. By using a refractor dome positioned around the upper parts of a
symmetrical point light source, beams of light could be fashioned and positioned to
illuminate the road surface.
The flux emitted in the lower hemisphere of the light source was uncontrolled, producing a
circular pool of light below the lantern. In this way, the road surface for some distance and the
environs around the lantern were illuminated.
This lantern design changed little during the next seventy years, although the glassware, refractor
assembly, bulb holder and lantern canopy became steadily simpler. Although open lanterns were
frowned upon by the mid-1950s (as no protection was afforded to the bulb nor the glassware
so both got dirty and required regular cleaning), the open dome refractor continued being
popular with local councils, still being made in the early 1980s.
In cases where no precise focusing mechanism was present, the filament of the bulb was either
located at the base of the refractor, or at the position marked on the refractor glass (usually
indicated by "LC" or "Lamp Centre"). In the case of high-pressure mercury bulbs, the arc
tube was positioned in the same place as the filament.
Name: BLEECO Worthing (100W) later BLEECO Open Type Conical Lantern 677
Date: Circa 1920s - 1950s
Dimensions: Width: 12 3/8", Height: 8"
Light Distibution: Uniform Distribution (BS 307:1927)
Refractor: Holophane Duo-Dome 4607 (75o)
Lamp: 100W GLS, later 60W GLS
History
The first recorded appearance of this lantern was in a
BLEECO catalogue from 1934. Named the Worthing, it was
the smallest of a family of lanterns, and took a 100W tungsten filament bulb.
The lantern’s name reflected the civic pride inherent in the UK’s towns and cities during this period. Council
members, or lighting engineers, with the help of a manufacturing firm's experts, often designed lanterns
and brackets for their towns, and representatives of Worthing probably specified, and perhaps, designed
this lantern. BLEECO’s styling was also evident including the white conical over reflector
and totally exposed refractor.
For its time, it had remarkably clean and modern lines, predicting the austere climate of the 1950s,
and not reflecting the contemporary art deco and fussy fashions of the 1930s. This understated,
simple exterior design continued inside the lantern; there were no elaborate bulb focusing mechanisms,
simply a threaded bulb-holder and lock nut.
At some point in the 1940s, BLEECO renamed and reclassified many of its products, switching
to numerical identifiers and functional names. The BLEECO Worthing became a member of the
Open Type Conical Lantern family and was designated the
number 677. The only design change (prompted by a British Standards Specification concerned with
street lantern design, BS 1788:1951) was to support the refractor dome from the top rather than use long
hooks to hold it by its base.
Identification
Early BLEECO lanterns have no manufacturers name or model number. Identification is
only possible by matching the lantern against those in the catalogues.
Later BLEECO lanterns featured "Made In England", a three digit number, and a square
symbol cast into the canopy of the lantern. Unfortunately, in these cases, the number isn't included
in the current range of catalogues, but the lantern can be identified by examples in earlier catalogues.
Popularity
The BLEECO Worthing was very successful lantern, escaping its
original home town of Worthing, and could be found distributed throughout the south of
England and further northwards. It was particularly common in various Sussex towns and cities,
with large installations in Worthing, Brighton and Hove, and notably used as the lighting
on Brighton’s Palace Pier.
Optical System
The BLEECO Worthing used a Holophane Duo-Dome refractor
to control the light distribution. This optical system divided the flux from the tungsten filament lamp
into two halves: light emitted from the lower hemisphere of the bulb was uncontrolled and symmetrically
illuminated the area below the lantern; the light emitted from the upper hemisphere of the bulb formed two
main beams directed by the prisms in the refractor. Therefore, the area around the base of the lantern
was well illuminated for the pedestrian and house owner (e.g. pavement, front gardens and parked cars)
and the road surface was illuminated at longer distances from the lantern for the car driver (e.g. bright
road surface, dark kerb edges etc.). Some flux was also redirected by the over reflector, forming a much
larger symmetric distribution around the lantern.
The Holophane Duo-Dome comprised of two interlocking pieces of prismed
glassware. The outer dome carried the vertical prisms and controlled the flux in azimuth; the inner
dome carried horizontal prisms and therefore controlled the flux in latitude. Whilst two pieces of
glass made the refractor large and heavy, and caused extra light loss (due to the flux having to
traverse two air-glass-air boundaries), the Duo-Dome was extremely suited for open lanterns
as the refractor had entirely smooth outer faces which simplified cleaning and maintenance.
Different sized Duo-Dome refractors were required for different wattages of tungsten filament
bulb. In the case of the Worthing, the 4607 refractor dome was the most
commonly used. Control of the elevation of the main beam required different inner domes, so they were
marked with the beam angle measured from the vertical. 75o was the most popular, suggesting
conformance with the uniform distribution system (BS 307:1927).
The provision for focusing was extremely poor: the continuous focusing system was error prone, compounded
that adjustment required removal of the refractor assembly (which was itself the only guide to correct focusing).
The BLEECO 677 In My Collection
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facing profile
I purchased this BLEECO Worthing from a reclaim yard near Cheadle. It was
in appalling condition as the refractor assembly was rusted and broken. However I bought it as it
featured long hooks holding the refractor dome (a feature I'd not seen before) and was mounted
on a complete BLEECO Brighton bracket.
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front profile
I completely stripped down the extremely corroded and fragile lantern. I removed
it from its original bracket, as I never intend mounting this lantern outside.
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trailing profile
Hampered by the bent and warped refractor assembly, the full restoration of the lantern
has not been entirely satisfactory. To force it back into shape would snap it in half.
Therefore, this lantern will always be extremely fragile, but is a good example of an early
BLEECO Worthing.
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canopy
Like most BLEECO lanterns, there are no identifying marks on the lantern’s canopy.
Formed of cast-iron, the canopy has two taps for two copper screws on which are threaded
wing nuts to support the over reflector and refractor assembly.
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pedestrian view
This BLEECO Worthing is fitted with a
Holophane Duo-Dome 4607 with beam angle at 75o from the downward
vertical and 2-way non-axial distribution (which appears to be the most common version). This
suggests the lantern adhered to the uniform distribution system (BS 307:1927).
It was painted green as this was the colour used by Brighton Council.
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vertical
This view clearly shows how the three copper hooks support the Duo Dome refractor
by its base. Unfortunately it also shows how the inner dome had been broken at some point in
the past; luckily the breaks were clean and I was able to stick the glass back together.
Despite this, and the problems restoring the refractor assembly, the lantern
itself brushed up well. As the lantern itself is a curiosity
(and not my best version of a BLEECO Worthing), I’ve installed
it on another curiosity: a broken BLEECO
Brighton bracket.
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interior
To focus the bulb, the threaded bulb holder was screwed into the lantern canopy to the required
height and then locked with a nut. This continuous focusing system was
required due to the variety of bulb sizes available in the 1930s and 1940s, and the errors in
tolerance between the bulb holder (mounted to the canopy) and the refractor (mounted to the refractor
assembly, mounted to the reflector, mounted to the canopy).
It was a poor system as the refractor had to be removed to adjust the bulb height against the
refractor (which you'd just removed!).
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