city of london vertical fluorescent lantern
This article was originally published in: Public Lighting Vol. 18, No. 75, June 1953
© Institution of Lighting Engineers
Left: The City of London lantern showing permanent City shield and Royal cypher specially attached for the period of
the Coronation festivities. (The pbotograph was taken from the top of a tower wagon).
The City of London entered something fresh in its annals with the introduction of a prototype installation
of five vertical wall mounted fluorescent lanterns of distinctive design and character in King Street,
leading to Guildhall, on Thursday, May 28, 1953. At Guildhall House, at the invitation of Mr. D. E. Erlebach, C.C.,
Chairman of the Worshipful the Streets Committee of the Corporation of London, an assembly of members of the Committee,
officers of the Corporation and representatives of the various parties associated with the project were hospitably
entertained prior to the switch-on at 9.30 p.m.
Addressing the assembly, the Chairman explained that much thought and consideration had been given to the
matter of installing new street lighting in the City, and with this in mind various experiments with fluorescent
lighting had been carried out. As a result, the Committee felt that the installation about to be switched on in
King Street was an introductory step which might well prove to be a lead to other Lighting Authorities who
favoured this particular type of lighting. From many aspects, not excluding that of economy, it was felt
that the initial installation would prove most satisfactory, and it was hoped that in the not too distant
future similar lanterns would be installed in many of the main streets of the City of London, the first to be
considered being the main traffic route from Aldgate to Holborn.
On behalf of the Committee, the Chairman congratulated the City Engineer, Mr. F. J. Forty, O.B.E., B.Se., M.I.C.E.,
on having conceived the idea from which this new lantern has emerged, and having himself seen an early prototype of
this fitting demonstrated to the Committee by the City Engineer, he had no doubt that its achievement this
evening would exceed even its early promise.
Mr. Francis J. Forty, the City Engineer, explained that during the war many of the street lamps and
apparatus in the City of London, as well as the buildings to which they were attached, were destroyed by
enemy action, and as a consequence a good deal of improvisation had been necessary to maintain a reasonable
degree of lighting until such time as a new scheme could be put into operation. Much common sense had been used
in the planning of the City's street lighting in the past, and whilst the chief form of illumination before the
war was provided by arc lamps, which then still maintained a high standard of efficiency, it was realised that,
even had not the war intervened, these would ultimately have to be replaced by installations on more modern lines.
After the war a new lighting scheme became essential. Many considerations had to be borne in mind, one of
the foremost being that, with the comparatively narrow and congested footways in the City, a system of central
suspension had hitherto been operated in order to keep the footways free of numerous obstructions, but this
method now carried with it many hazards and difficulties in connection with the maintenance of modern installations.
The merits of various street lighting systems were studied, and ultimately experiments were carried out with
fluorescent lamps, to judge their suitability in City streets, and to gain experience of maintenance problems
and relative costs. A scheme was prepared for relighting about ten miles of main streets with standard fluorescent
lighting fittings, which was estimated to cost about £100,000; but he felt that an expenditure of this magnitude
merited the use of specially designed lanterns suited in character, appearance and performance to the City of
London. He considered that a vertical lantern for wall mounting could be constructed to his suggested design.
Siemens Electric Lamps and Supplies Ltd. were invited to prepare drawings for such a fitting, and after
several joint consultations on matters of aesthetic and practical detail with representatives of that firm
and the London Electricity Board, the present fitting has evolved.
Mr. Forty expressed appreciation of the cooperation of Mr. C. R, Bicknell, of Siemens; Mr. G. H. Fowler,
of the London Electricity Board; Dr. W. E. Harper and his colleagues of the I.C.I. who designed the refractor
system, and of his own assistant, Mr. A. S. Tapsfield (a Past President of the Association of Public Lighting Engineers),
who had coordinated all parties and aspects of the project during its progressive stages.
Mr. C. R. Bicknell, of Siemens Electric Lamps and Supplies Ltd., welcomed the opportunity of paying
a tribute to those who had helped them in the successful production of the lanterns that the Chairman
was about to switch into service.
He recalled that it was almost exactly six months since the City Engineer asked for a vertical,
wall mounting fluorescent lantern to meet the special difficulties that pertain to the lighting of
the City's streets. After a very little reflection Siemens became enthusiastic workers in the development
of this new idea.
The result was a lantern, embodying a specially designed refractor system of light control that introduced
something new to the public lighting world, conceived in the City of London, designed in the City of London,
and it was appropriate and a source of pride to Siemens that the first installation should appear in the City of London.
It was interesting to note that, on a much earlier occasion, Siemens pioneered electric street lighting in the
City of London when, some 70 years ago, they erected a trial installation of arc lamps on 80-ft.
lattice poles outside the Royal Exchange.
Siemens greatly appreciated the constructive and always helpful discussions that they had had with the
City Engineer, and with his Public Lighting Superintendent, Mr. Tapsfield, also with Mr. Fowler of the London
Electricity Board, and members of his staff. They wished, also, to acknowledge the invaluable help of Dr. Harper,
Mr. Collins and their colleagues of the I.C.I. Plastics Division in the design of the optical system.
The fact that the lanterns would be switched on only six months after Mr. Forty conceived his idea was
in itself a tribute to team work of a very high order, team work in which everyone concerned had tried
to pull just that little bit more than his full weight in the interest of a common cause.
Mr. G. H. Fowler, of the London Electricity Board, pointed out that, in arranging this experiment, the
Corporation of London were following a tradition of pioneer work in street lighting dating from at
least as far back as 1807, when gas lamps were first introduced in Golden Lane, and undoubtedly before
that when oil lanterns were hung outside people's houses in the City.
He mentioned the arc lamps which were installed along Holborn Viaduct in 1878, and briefly traced
the lead taken by the Corporation right up to the present experiment.
The predecessors of the London Electricity Board had always co-operated with the City Corporation in
previous experiments, and the London Electricity Board were happy and honoured to be associated
with the present project. The Corporation could rest assured that any further help they required
in the future would be readily forthcoming from the Board.
Colonel W. W. Dove, Chairman of the City Coronation Decorations Committee, thanking the Chairman and members
of his committee for their hospitality, stated that he felt the aesthetic appearance of 'the lanterns
deserved most favourable comment, and he was particularly impressed with the permament fixature of the City Shield
which had been incorporated in the perspex cover, as well as the royal cypher which had been attached for the period of the
Coronation festivities.
The lanterns, when switched on, adequately fulfilled all expectations, providing a very even illumination ove
both the carriageway and footways, and all concerned in the design, manufacture and installation are to be congratulated.
Details of the construction of the new "City of London" lantern are as follows: Incorporates all the features necessary for
first-class performance combined with simplicity of design ensuring easy service and maintenance, is self-contained and compact.
The auxiliary gear is completely housed within the lantern; ready wired to connect the supply leads to terminal blocks.
This new development has been based on thorough and extensive experiments backed by Siemens' well-known research organisations.
Construction
The construction consists of a pair of interchangeable cast aluminium end plates connected by a "U" channel spine.
A detachable control gear tray carrying switch or instant start control gear is provided. Adequate space in the base
of lantern for mounting fuses, time switch or relay. The gear tray, hinges, and various components are all assembled,
pretreated and stove enamelled after assembly. The perspex cover and end features are hinged to facilitate access to
the interior and complete ladder maintenance can be carried out simply and quickly. Quick release retractable lampholders
are fitted and heavy duty non-hygroscopic gaskets render the lantern dustproof and weatherproof.
Lamps
Three 80-watt 5-foot Sieray fluorescent tubes.
Light Control
This is provided by a special scaled-in refractor system.
Mounting
Suitable for mounting vertically on walls. The fixing centres are vertical and can be varied over a considerable
range to suit site conditions. Suitable stand-off brackets can be supplied to avoid any decorative features protruding
from the walls. The lantern can also be fixed to concrete or steel columns.
For ease of Erection
The lantern is so wired that the gear tray can be removed at ground level enabling the shell of the lantern
to be put in position and erected separately by two fixing points.
Weight
Total weight 96 lb. Without control gear 70 lb.
Control Gear
The necessary control gear for instant start is within the lantern and comprises the following : Three U.812 Combined Choke Starting
Transformers. Three C.70 0.02 Radio Interference Suppressors. Three C.800 P.F. Correction Capacitors.
Bulk P.F. Correction Condensers can be supplied if required. Switch start equipment is also available.
© Institution of Lighting Engineers
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