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ilp archive : journals

public lighting no. 35 vol. 9
October-December 1944

Editorial p101
The Lights Went On p101
There were many expressions of appreciation in the papers after the new standard of lighting was permitted on Sunday, September 17th. Lighting engineers had worked wonders taking full advantage of the relaxation and modifying ARP/37 fittings or installing new lamps.
Lighting: ARP

Relief For Londoners p101
The unexpected relaxation of the lighting order for the London defence regions was met with mixed feelings. For security reasons, London was expected to stay "dimmed out". The lighting authorities within the area turned their attention to the work of preparing for a full "light up". Much work had been accomplished and a vast amount of full street lighting could be turned on in London within the repeal of the lighting restrictions order. To go back over this useful work and reinstate another order of lightign would be both expensive and wasteful. Therefore many authorities have decided to have little or nothing about the matter. There was a feeling among the wide circle of professional lighting engineers that insufficient consideration had been given to them. Surely it was not too much to ask His Majesty's Government to take professional lighting engineers into their confidence.
Lighting: ARP

Approved Designs For Lamp Columns p101
In 1938 the Royal Fine Arts Commission, at the request of the Ministry Of Transport, expressed willingness to approve (or otherwise) the artistic merits of designs for street lamp columns. A selection of designs is now available. In considering the designs, the Commissioners have aimed at simplicity. The days of the ultra decorated lamp column has gone - what is wanted is a plain design having pleasing sweep or curve to the lantern. The idea is to make the column and lantern less noticeable. The general trend will be "the column lighter, but the lamp brighter."
Lighting: Design

Cartoon p101
Cartoon by Gittens from the London Evening News
Lighting: Social Comment

British Standards Institution p102
Report from their Annual General Meeting

Personal p102
Mr. W. P Lilwall, Borough Electrical Engineer, Fleetwood was re-elected without opposition as President, Incorporated Municipal Electrical Association.
Lighting: Personnel

New President Of The I.E.S. p102
Mr. Ernest Stroud has been chosen as President of the Illuminating Engineering Society for this year. He is the general sales manager of Holophane Ltd and chairman of the Street Lighting Section of the Electric Light Fittings Association. During the war, Mr. Stroud has served on various committees of the B.S.I., including street lighting, portable photometers, light distributions, lighting fittings, A.R.P. street and factory lighting.
Lighting: Personnel

Suggestions For Modifying Existing Gas Street Lighting Equipment To 0.02f.c. p102
A circular distributed by the Institution of Gas Engineers gives useful hints how to modifiy equipment to conform with the new "dim out" to the level of 0.02 f.c. at ground level.
Due to the differences in installations throughout the country it's only possible to give a general outline. A convenient method of obscuring the lower portion of the lamp is by applying whitewash or thin white paint stippled to give an even dispersion with a strip - about ¾" to 1" - of clear glass. A black "cut off" band is painted around the top of the lantern.
A disadvantage of the colour wash or paint is the necessity of removal when pre-war lighting reinstated. This may be overcome by the following suggestion: A No. 1 Bijou mantle is used, and the glass of the square lantern is blackened down to a position level with the bottom of the mantle (as originally suggested). A thin metal disc, 2¾" in diameter, suspended horizontally and centrally below the mantle produces a "penumbra" effect which evens out the illumination on the road surface.
Lighting: ARP, Lighting: Specifications

Street Lighting Designs For Post-War Installations p103
The General Electric Company Limited
The GEC will supply lanterns of the pre-war types such as the Wembley prismatic dome refractor lanterns; and the Difractor and Oxford lanterns which use a prismatic bowl. To assist production it will be necessary to restrict the range of replacement lanterns and so the company will only produce the most popular designs.
Where lanterns in a particularly old installations have been damaged, the remainder should be re-grouped in some less important roads, the main thoroughfares then being re-equipped with lanterns of a more modern type.
For the modern lantern with its carefully controlled distribution, the casual treatment of earlier years is no longer adequate. The mechanical design must ensure that the precise limits of the optical system are regularly attained in production and maintained in service.
The mechanical requirements of a street lighting lantern can be analysed as follows:
Mechanical Design: Precise, rigid assembly.
Service Requirements: (1) Resistance to weather (2) Resistance to corrosion (3) Ability to withstand shaking and vibration (4) Satisfactory operating temperatures.
Maintenance Requirements: (1) Simple erection and wiring (2) Ease of cleaning and freedom from dirt collection (3) Unvarying performance without adjustment.
Appearance: Unobtrusive and attractive.
The period of the war has allowed the designs to be brought up-to-date by the incorporation of minor improvements in the mechanical detail and finish.
Lanterns in the new range are based on the following:
Modern Design, Engineering Construction: Neat, pleasing appearance, robust construction and unsurpassed optical systems are the keynotes of the new lanterns. They are the result of a close co-operation of engineers intent on the best possible mechanical construction and modern artists conscious of the importance of daylight appearance of the lantern.
Logical Side Mounting - They are arranged for side mounting, which eliminates the terminal box, gains mounting height and ensures freedom from rain entry. The bracket, which must be 1¼" gas barrel, slides into the body of the lantern where it clamped by two drawbolts. No threading or tapping of the bracket or lantern is necessary.
Light alloys - Extensive use has been made of light alloys in the lantern's manufacturer. By their use, weight has been reduced by 25%. In addition, "sympathetic" metals have been selected to avoid corrosion and electrolytic action.
Difractor, Horizal, Total Enclosure Type (Blown-Glass Cut-off) and Uniway.

Keith Blackman Limited
Supervia, Keith Suspension Lamp 808 and Keith Lamp 805N.

Engineering And Lighting Equipment Company Limited
Orbital, Lanark, Golden Ray, Vapoura, Highway and Pinnacle.

William Sugg And Company Limited
Rochester, Littleton, London B2, Windsor, Folkestone and 8000 Lamp.

Lighting: Future, Lighting: Luminaires

The Lights Go Up! Some Impressions Of The Public's Reaction To The Improved Street Lighting p109
Sunday, 17th September 1944, was a red letter day in the annals of Public Lighting. The partial lifting of restrictions concerning street lighting and domestic black out came as a great relief to several millions of people throughout the country. To children the relighting of the street lamp came as a real novelty. Parents were seen parading the streets with their children to see the novel sight of darkened streets turned into fairlyland - so it seemed to the children.
Reports were sent in from Blackpool, Farnborough, Hull, Bedford, Chester, Rhondda, Oldham, Preston, Halifax, Wigan, Hinckley, Edinburgh, Leicester, Woking, Croydon, Motherwell and Wishaw, Bristol, Bradford, Stroud, Leamington Spa, Douglas, Bedwellty and Rochdale. Details in the Installations section.
Lighting: ARP, Lighting: Installations

The Patent Situation Just After The War by S. T. Madeley p114
Considerable sums are involved as regards enemy-owned patents, around 1 to 2 million. A well qualified committee is now considering amendment to the British Patents Act. A long description is given of changes to the patent system during and after the First World War.
At the comencement of the Second World War, the Patents, Designs, Copyright and Trade Marks (Emergency Act) 1939 came into force. This was followed by a series of Statutory and Patent Office Rules and Orders. These gave the Government practically unlimited power over inventions for which Patent protection is sought.
The Comptroller is given powers to revoke or amend existing Licences under enemy patents and to grant emergency licences under Patents of the same nature. Royalties are paid to the Custodian of Enemy Property. The Comptroller can also grant extensions of time for procedure.
At the beginning of the war the General Licence issued by the Board Of Trade permitted carefully controlled correspondence with enemy countries related to Patent matters. This was found to be unsatisfactory. By the subsequent General Licence issued in April 1942, proceedings regarding enemy-owned British patents, granted and pending, were practically reduced to payment of renewal fees on granted patents by non-enemies who were licenses or part-owners. Consequently there are no many patent applications based on corresponding patent applications in enemy and enemy occupied countries and which are awaiting the requisite funds before filing.
Numerous patent applications based on British ones are also due for filing in Germany when circumstances permit.
The British Patent Office is already overburdened with work owing to shortage of staff.
In Germany, the Patent Office appears to have been carrying on with much of its usual efficiency. There is evidence to show that British-owned businesses have been functioning in Germany and technicians in occupied countries have had to give their services to Germany.
Lighting: Legal

The I.E.S. President Mr. E. Stroud p115
The Illuminating Engineering Society held a sessional meeting at the E.L.M.A. Lighting Service Bureau on Tuesday 10th October. Mr. E. Stroud was inducted into the Chair of the Society. The paper was a detailed record of the history and work of the Society from 1909 up to the present time.
It was founded by Mr. Leon Gaster, who until 1928, was the Honorary Secretary. Few engineering firms had established departments to deal with illumination and there were few who could be considered experts. Photometry was at the laboratory stage and there was little apparatus availabel for the measurement of illumination.
The inaugural meeting was held at the Royal Society of Arts on November 18th, 1909. Outstanding in those early pioneering years was Mr. A. P. Trotter (President 1917-1920) who, with Sir William Preece, was responsible for the design of the earliest illuminating photometer in this country and whose treatise on "Illumination: Its Distribution And Measurement" is a classic. Trotter also dealt with iso-lux curves, now commonly used in Street Lighting calculations.
Much pioneering work was done in those early days by very few people. There was no general knowledge of the values of illumination that existed in typical buildings and the instruments available for the measurement of illumination were few and cumbersome. The period saw the introduction of the metallic filament lamp and the preheated inverted gas burner, which effected such a great advance in light output and efficiency as compared with their predeccesors. During this early period, reports on the lighting of schools and libraries were issued by joint committees which, in conjunction with other leading engineering bodies, drafted a standard specification for Street Lighting.

The First Great War
Just prior to the Great War, the "Half-Watt" electric lamp was introduced, the forerunner of the present "Gasfilled" Tungsten Lamp. It was only made in the larger sizer, but owing to the increased brilliancy of the filament, introduced new problems in illumination and opened up a promising field for artificial lighting. The society made useful contributions for the war effort. And in 1915, the first of a series of reports was issued by the Departmental Committee on Lighting in Factories and Workshops.

Stret Lighting
In 1922-23, a B.S.I. Committee was set up to produce a specification for Street Lighting. It produced the first Street Lighting Specification, 307/1927, which was revised in 1931, and is further being considered (after the MOT Final Report, 1937). The Street Lighting Committee is under the chairmanship of Dr. C. C. Paterson.

The floodlighting of the London Buildings was organised by Mr. Percy Good, director of the British Standards Institute, and carried out by lighting firms at their own cost. This was repeated for the Silver Jubilee and the Coronation and will undoubtedly form a large part of the Peace Celebration. During 1939, a great amount of work was carried out by the Ministry Of Home Security by Committees of the Society and prominent members. The research on A.R.P. lighting had the attention of 24 committees and approximately 100 members. Much of the work done is evident in the series of A.R.P. Specifications published by the B.S.I.

Closer Co-Operation Internationally
In the post-war period, they look forward to much closer contact with the Commonwealth and the United States. This should have a far-reaching effect on the dissemination of lighting knowledge and on the Society in particular. We have close contact with the American Society through the National Illumination Committee and the International Commission on Illumination by the International Illumination Congresses held every four years.
Lighting: History, Lighting: Specifications

The Press Adds Its Praise p116
Extracts from The Sheffield Telegraph. Details in the Installations section.
Lighting: ARP, Lighting: Installations

A Full-Dress Rehearsal Of Post-War Street Lighting p117
Lighting engineers and municipal authorities were invited to a demonstration of full street lighting at The Engineering And Lighing Equipment Company Limited. The occassion became almost festive as the people of St. Albans and their children made their way to scene. Some of the children had never seen street lightings working before: "I shouldn't mind going out in the 'black-out' if the lights were like these."

General Description
The demonstration was seven weldless steel standards erected in Campfield Road, St. Albans, in staggered formation, at spacings 150'. Each standard had four different lighting units, which could be switched singly. Direct visual comparisons could be made at intervals of a few minutes. The fittings were standard ELECO types.

Light Sources
Three different types of electric discharge lamps were used for the demonstration. They have at least three outstanding characteristic: High Luminous Efficiency (they give from 2.5 to 5 times the light output of ordinary tungsten filament lamps); Long Life (1500 or 2500 hours according to type rather than the 1000 of tungsten filament lamps); Colour (They do not give white light, but they don't need to for public lighting).

Mercury Lamps
These lamps are made in four ratings: 80W, 125W, 250W and 400W. The 80W and 125W are designed for operation in the vertical position and the 250W and 400W operated either vertical or horizontal. For horizontal, it is necessary to equip the lantern with a magnetic control, which is located adjacent to the lamp, and prevents distortion of the discharge luminous column. The initial luminous efficiencies are 38, 40, 36 and 45 lumens per watt i.e. about 2.5 times that of the tungsten filament lamp. Average life 1500 hours. Warming up time is 10 minutes. If switched off when hot then must cool before they relight.

Fluorescent Lamps Three ratings of fluorescent mercury lamps are available at 80W, 125W and 400W. Each is for vertical burning. The initial luminous efficiencies are 38, 40 and 38 lumens per watt. The efficiency of the 400W size is somewhat lower than its non-fluorescent counterpart but the light colour is somewhat whiter. Average life 1500 hours. Warming up time 10 minutes. If switched off when hot when must cool before they relight.

Sodium Lamps
Three lamps have been developed in a range of four ratings 45W, 60W, 85W and 140W. The smallest can be used either vertically or horizontally, but the three larger ones are for horizontal use only. Each lamp operates inside a detachable vacuum jacket which has a life of three lamps so replacement lamps may be used in the same vacuum jacket. The lamps have remarkably high initial luminous efficiencies of 55.5, 65.0, 71.5 and 71.5[?] lumens per watt respectively which is 3 to 5 fives that of the tungsten filament lamp. Average life is 2500 hours. Warming up time 10 - 20 minutes according to rating. If switched off when hot, will relight immediatley. Relatively insensitive to voltage variations. The light source of the 140W rating consists of a "U" bend tube about 18" long, operating horizontally, with a low brightness of 10 c.p. per sq. cm., which reduces the risk of glare. The light colour is golden yellow in which the eye functions with nearly its maximum sensitivity. The monochromatic nature of the light obviates perception of reflected colours and increases brightness constrasts and visual acuity.

Judging An Installation
The efficacy of any installation should not be judged by the illumination intensity measured on the road surface. This is no gauge of the visibility. Judgement should be based upon the degree of visibility obtained with economic consideration. After many comparisons and tests, many municipal authorities have preferred to install sodium lighting. The ELECO demonstration enabled the visibilities provided by the three different types of electric discharge public lighting to be compared.

Mercury Lighting
Seven 400W mercury lamps operating vertically in ELECO Orbital lanterns at 25' high, 150' apart, with 3'6" overhang. B.S.S. test point illumination intensity 0.22 ft. candles.

Fluorescent Lighting
Seven 400W fluorescent lamps, vertically burning, were fitted with in ELECO Hamilton lanterns at 25' high, 150' apart with 6' overhang. Due to the difficulty controlling the light from these lamps, due to the large dimensions of the luminous source, and the lower efficiency of the lamp, the B.S.S. test point illumination is lower at 0.16 ft. candles. This type of lamp has not been so widely used for public lighting.

Sodium Lighting
Seven 140W Philora sodium lamps were fitted in ELECO Golden Ray units, at 25' high and 150' apart, with 6' overhang. The B.S.S. test point illumination intensity was 0.21 ft. candles.

Sodium Lighting (Side Street)
Seven 50W Philora sodium lamps in ELECO Golden Ray units mounted on the main standards at 14'6" high and 150' apart.
Lighting: Installations, Lighting: Lamps, Lighting: Luminaires

Modified Gas Lighting p118
Pictures and descriptions of "Dim Out" gas lighting in Leamington and Cambridge. Details in the Installations section.
Lighting: ARP, Lighting: Installations

Lighting Progress In Glasgow p119
In the recent "Glasgow Advancing" Municipal Exhibition organised by the Glasgow Corporation to show present activities and possible post-war developments, the Lighting Department displayed a number of exhibits. The main theme demonstrated the principle of central control used with public lighting for both street and tenement-stair lighting. A map of the Partick district of the city showed the main pilot control lines radiating from the control station. Associated with the exhibit were impulse and cascade relays.
The Lighting Department is responsible for the maintenance and lighting of all the public clocks in the city and two methods of dial lighting were shown: in one a sodium lamp was mounted behind the translucent face; and in the other a spotlight was used to project light on the front surface of the face. Both methods were used successfully in 1939. Similarly examples of internally and externally illuminated street names were shown.
Two models showing special features aroused considerable interest: red illuminated panels in the kerb reveal projecting footpaths by night (at one danger spot in the city such a device has been in use for some months); and the siting of street lighting units on dual-carriageway roads with each carriageway treated separately for lighting, having a staggered system (as per the Final MOT Report).
Another exhibit was the malicious damage to the Department's equipment. This damage annually costs hundreds of pounds to the rate payers. Examples shown included a hefty spanner found inside a gas lantern, damaged traffic signals, screens attached to war-time lights and torn off, and gas mantles broken in common stairs by persons inserting spills and tapers to get lights.
Lighting: ARP, Lighting: Control, Lighting: Installations

High Mountings Give Improved Gas Lighting p119
Details of a 1939 improvement scheme in Leamington.
Lighting: Installations

Bishops Stortford p120
Details and pictures of the pre-war scheme in Bishops Stortford.
Lighting: Installations

Things To Come p121
Details of two other Combined House Service Units by Siemens.

A Useful Pamphlet For Lighting Committees p121
The pamphlet titled Public Lighting In The City And Highway, designed primarily for members of public lighting committees as a guide for the requirements of good street lighting after the war, has just been issued. It was the result of a comittee on with both the Illuminating Engineering Society and the Association Of Public Lighting Engineers were both represented.
Lighting: Publications

Go-Getters p121
Manchester has just decided to light its side streets as well as it main streets. (Incudes dig from Sheffield's Daily Telegraph).
Lighting: Installations

Situations Vacant p121
Adverts for a Lighting Engineer and a Public Lighting Expert
Lighting: Installations

Winnipeg's Tribute To London p121
"Festoon lights will blaze over Portage Avenue and Main Street next Saturday and Sunday nights and flags will wave along the two thoroughfares to mark the turning on of London's lights, Sunday."
Lighting: Events, Lighting: Installations

Light, Vision And Seeing: A New Book Published In New York By Matthew Luckiesh p122
Review of Luckiesh's book.
Lighting: Publications, Lighting: Theory

Cartoon p122
Cartoon from the London Evening News.
Lighting: Social Comment

Adverts: Poles Ltd, The Association Of Metal Sprayers, Stanton Ironworks Co., Ltd, Siemens Electric Lamps And Supplies Ltd., Metropolitan Vickers Electrical Co. Ltd, Engineering And Lighting Equipment Co. Ltd., Holophane Ltd., British Commercial Gas Association, British Electrical Development Association, Inc, Philips Lamps Ltd., The British Thomson-Houston Co. Ltd., Automatic Telephone And Electrical Co., Ltd., William Sugg And Co., Ltd., The Lighting Service Bureau, Walter Slingsby and Co., Ltd., The Horstmann Gear Co., Ltd., British, Foreign And Colonial Automatic Light Controlling Co., Ltd., Foster And Pullen Ltd., Sangamo Weston Ltd. and The General Electric Co., Ltd.