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BLEECO Worthing (200-300W)
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 (200-300W GLS)
Date: Circa 1920s - 1950s
Dimensions: Width: 18", Height: 11"
Light Distibution: Uniform Distribution
Refractor: Holophane Duo-Dome 4607 (80°)
Lamp: 200-300W GLS
History
The only recorded appearance of this lantern was in a
BLEECO catalogue from 1934. Named the Worthing, it was
the largest of a family of lanterns, and took a 200-300W 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.
Unlike its smaller sibling, the larger Worthing had a scalloped, decorated canopy made
from two separate castings. It also had an exterior lamp focusing mechanism; two knurled nuts on the
top of canopy allowed the lampholder bridge to be positioned within the lantern.
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 larger 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.
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 Worthing In My Collection
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facing profile
This lantern was rescued from the skip at Brighton Council's depot. It was complete
and in relatively good condition having been sawn off its original bracket.
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front profile
These pictures show the lantern after restoration and painted in its original green colour.
It's fitted with a Holophane Duo-Dome 4607 refractor with
80° 2-way asymmetric non-axial distribution.
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trailing profile
The lantern was a larger version of the popular Worthing lantern and was designed
for 200-300W GLS lamps. However, I've fitted this lantern with a 100W GLS lamp.
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canopy
The canopy is made of two cast iron sections with knurled nuts on the top to allow
the bulb holder assembly to be moved up and down, allowing correct focusing of
the bulb.
Like all BLEECOs, the canopy has neither the maker's name nor
any model number.
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pedestrian view
The spun enamel secondary reflector is in excellent condition. It supports the
refractor assembly and is in turn supported to the two-piece canopy by three
brass wing nuts.
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vertical
The lantern has been fully restored and fitted to a
BLEECO Brighton And Hove type
bracket. This was a popular bracket-and-lantern configuration in Brighton.
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interior
The lampholder is fitted to a central bridge which engages with the screwed threads of either knurled nut
assembly. Turning the knurled nuts up or down would cause the lampholder bridge to move as well. Both
sides of the central bridge could be moved therefore allowing the lamp to levelled.
The mechanism was seized due to corrosion and lack of use but it only required some heat and some
penetrating oil to get it working again.
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