Annual Conference at Glasgow
September 4th-8th, 1939

This conference was cancelled due to the start of the Second World War. However the conference programme and papers were printed.

The President's Address was printed in Public Lighting #15.

Note that the programme is incomplete and some pages are damaged or missing. (Adverts are missing for Foster And Pullen, Ltd. and Horstmann Gear Co., Ltd.)

Abstract: Descriptions of lanterns and equipment displayed by Siemens Electric Lamps And Supplies Ltd., The Electric Street Lighting Apparatus Co., The British Thomson-Houston Co. Ltd., The General Electric Co., Ltd, Edison Swan Electric Co. Ltd., Philips Lamps, Ltd., Holophane, Limited, The Brighton Lighting And Electrical Engineering Company, Ltd., REVO Electric Co., Ltd., William Sugg And Co., Ltd., W. Parkinson and Co., Foster And Pullen Ltd., Keith Blackman Ltd., Walter Slingsby and Co., Ltd., Automatic Telephone And Electric Company Limited, Bromford Tube Co., Ltd., Standard Telephones And Cables Ltd., Concrete Utilities Ltd., Whelmer Gas Mantle Co., Venner Time Switches Ltd., Radiovisor Parent Ltd., British Sangamo Co. Ltd., Peebles And Co., Ltd., British Foreign and Colonial Automatic Light Controlling Co. Ltd., Poles Ltd, British Electrical Development Association, C. H. Kempton and Co., Ltd., Engineering And Lighting Equipment Co., Ltd., Metropolitan Vickers Electrical Co., Ltd., British Commercial Gas Association, W. T. Henley's Telegraph Works Co., Ltd., Stanton Ironworks Company Ltd., Gas Meter Company Ltd., Metropolitan Pipe And Pole Company Ltd., Wardle Engineering Co. Ltd., Simplex Electric Co. Ltd. and William Edgar & Son Ltd..

Provisional plans (as outlined in Public Lighting #14 were for the following out-door exhibitions: Foster And Pullen Ltd. (West Campbell Street), William Sugg And Co., Ltd. (West George Street), C. H. Kempton and Co., Ltd. (Vincent Street), W. Parkinson and Co. (Vincent Street), Keith Blackman Ltd. (Shamrock Street), The Electric Street Lighting Apparatus Co. (Argyle Street East), Metropolitan Vickers Electrical Co., Ltd. (West George Street), The Brighton Lighting And Electrical Engineering Company, Ltd. (Bothwell Street East), Simplex Electric Co. Ltd. (Holm Street), The British Thomson-Houston Co. Ltd. (Cadogan Street), The General Electric Co., Ltd (Waterloo Street), Edison Swan Electric Co. Ltd. (Bothwell Street West), Siemens Electric Lamps And Supplies Ltd. (Argyle Street West), Holophane, Limited (Bath Street East), Engineering And Lighting Equipment Co., Ltd. (West Regent Street), REVO Electric Co., Ltd. (St. Vincent Street) and Wardle Engineering Co. Ltd. (Bath Street West)

Dual carriageway lighting displays were also planned for the Great Western Road and Edinburgh Road: The General Electric Co., Ltd (Great Western Road), Siemens Electric Lamps And Supplies Ltd. (Great Western Road), Engineering And Lighting Equipment Co., Ltd. (Great Western Road), REVO Electric Co., Ltd. (Edinburgh Road), Metropolitan Vickers Electrical Co., Ltd. (Edinburgh Road) and Simplex Electric Co. Ltd. (Edinburgh Road)

Adverts: Radiovisor Parent Ltd., Stewarts And Lloyds, Ltd., Siemens Electric Lamps And Supplies Ltd., Amal, Ltd., The Electric Street Lighting Apparatus Co., Peebles And Co., Ltd., The British Thomson-Houston Co. Ltd., Edison Swan Electric Co. Ltd., REVO Electric Co., Ltd., Holophane, Ltd., The Brighton Lighting And Electrical Engineering Company, Ltd., William Edgar & Son Ltd., William Sugg And Co., Ltd., Newport And South Wales Tube Company Limited, Keith Blackman Ltd., Walter Slingsby and Co., Ltd., Automatic Telephone And Electric Company Limited, Bromford Tube Co., Ltd., Falk, Stadelmann and Co. Ltd., Standard Telephones And Cables Ltd., Philips Lamps, Ltd., Concrete Utilities Ltd., Whelmer Gas Mantle Co., Metropolitan Pipe And Pole Company Ltd., Venner Time Switches Ltd., British Commercial Gas Association, British Sangamo Co. Ltd., Stanton Ironworks Company Ltd., Automatic Light Controlling Co. Ltd., Poles Ltd, Gas Meter Company Ltd., W. Parkinson and Co., Measurement Limited, C. H. Kempton and Co., Ltd., Metropolitan Vickers Electrical Co., Ltd., Metropolitan Vickers Electrical Co., Ltd., W. T. Henley's Telegraph Works Co., Ltd., Wardle Engineering Co. Ltd., Simplex Electric Co. Ltd., Engineering And Lighting Equipment Co., Ltd., British Electrical Development Association and The General Electric Co., Ltd.

Provisional papers (as planned in Public Lighting #13):

Tuesday, September 5th, 1939

Presidential Address by Mr. E. J. Stewart, M.A., B.Sc. (Inspector Of Lighting Of Glasgow)

Lighting In Glasgow by Mr. J. M. Ward

Wednesday, September 6th, 1939

Modern Gas Street Lighting by Mr. A. V. Horsfall

Illumination Of Roundabouts, Bollards etc by Mr. K. Sawyer

Lighting Of Bends And Junctions by Mr. F. F. Middleton

Thursday, September 7th, 1939

Lecture Demonstration by Professor S. Parker Smith

Friday, September 8th, 1939

New Installations In Dublin by Mr. F. X. Algar

Some Aspects Of Modern Development In Electric Lamps For Street Lighting by Mr. L. J. Davies (B.T.H Co. Ltd.)

Tuesday, September 5th, 1939

Presidential Address by Mr. E. J. Stewart, M.A., B.Sc. (Inspector Of Lighting Of Glasgow)

Lighting In Glasgow by Mr. J. M. Ward

Wednesday, September 6th, 1939

Modern Gas Street Lighting by Mr. A. V. Horsfall

Engineering Principles In Lantern Design by Mr. J. G Christopher and Mr. J. S. Smyth B.Sc.(Eng.)

Thursday, September 7th, 1939

Lecture Demonstration by Professor S. Parker Smith D.Sc., M.I.E.E., A.M.Inst.C.E.

Friday, September 8th, 1939

Illumination Of Roundabouts, Bollards etc by Mr. K. Sawyer

Lighting Of Bends And Junctions by Mr. F. F. Middleton

Some Aspects Of Modern Development In Electric Lamps For Street Lighting by Mr. L. J. Davies (B.T.H Co. Ltd.)

Mr. E. J. Stewart, M.A., B.Sc.
Inspector Of Lighting Of Glasgow

Keywords: .

Tuesday, September 5th, 1939

Summary published in: Public Lighting, Vol. 4, No. 15. September 1939

Abstract: xxxx.

Street Users As Judges Of Lighting
Persons see differently the same street, by day or by night, because they look for different things.

Noticeability Of Lighting Differences
The practical question about noticeability becomes: "What is that difference between one lighting installation and another which is obvious to the majority of those whose opinion counts in deciding how a street is to be lighted?" The answer depends, not only on the technical characteristics of the installations, together with the characteristics of the streets, but on the different interests of users of any street, their different previous acquaintance with street lighting etc. The answer depends too, on the different prepossessions, the different mental and emotional contents and reactions of various observers, leaving out the account the many users of streets who never notice the lighting at all.

Obvious Changes Of Appearance
With our close spacing of 75', lamps mounted at 10½' may give complete visibility for at least 100 yards where carriageways, footways and buildings reflect well. Yet the call continues for high mounted lamps. Their power and distriubtion is superior; I believe the demand is not entirely based upon these gains, but upon the different in pole and height which are so much more obvious. Some of the success of discharge lamps is probably on account not only of the actual increase of light but of the notable change of appearance.

Obvious Changes Of Source
Among our 25' or 26' installations are streets which in relation to their form, their surface and their traffic, are well lighted by 200W filament lamps at our 120' spacing. In some others 300W are necessary. In some of these a change from 200W to 300W would satisfy; in others the jump would need to be from 200W to 500W both to give the desirable general brightness and to make obvious that there had been an improvement. One street, with wide carriageway lit passably by 200W lamps near the kerbs, was converted into two separate carriageways. It was not convenient to add rows of lamps towards the centre-line. And increase at the existing points to 500W lamps plus directive apparartus was required to produce distinct improvements by greater brightness of the source and by greater brightness over the road surface. On the other hand even if a more expensive fitting produces a theoretically more appropriate set of distribution curves than another, is it worth while if the resultant difference from a cheaper type is generally not noticed by users of the street?

Noticeable Difference In Height
What difference in mounting height is noticeable by the public? I am doubtful whether a change in height alone from 9 or 10½ to come within the Specification would be noticed. I know examples where, combined with a doubling of light output, it was unnoticed. Generally any changing of height is accompanied by change of candle-power in some direction, even if the spacing remains unchanged.

Spacing
As regards spacing, liability to criticism is closely linked with the lighting output; but while any distance up to 240' or even 300' may pass muster, according to the power and the road, yet when low-mounted units are as much away from our ususal 75' spacing as 120', this is just about like to be noticed, at 150' is likely, and at 180' is very likely - and likely to ensure the request for "big" lamps.

Age
The reduction in light output by age becoems noticeable for filament lamps at about 1000 hours and is the order of 10%. This is noticeable if the lamp is alongside a new lamp. A drop of 15% at 1500 hours may be noticeable along. At what number of hours' burning, corresponding with drop in efficiency, should we remove the various sources? Perhaps when the drop becomes obvious to the user of the street, or the lighting department inspector?

Dirt
A reduction in light output, due to dirt, which is likely to be noticeable to a trained observer, is about 15%, produced in a city atmosphere after about two weeks. Probably distinct noticeability begins at a reduction of about 20%. In Glasgow, all low-mounted gas lanterns and open electric reflectors should be kept reasonably clean. There is no difficulty in noticing that any of these is dirty or becoming dirty. The spread of high-mounted electrical units ahs compelled the adoption of periodical cleaning with regular shifts of men doing this all the time, takign the place of the general purpose lamplighter.

Variety Of Judgment
We generalise about lighting on the basis of the average eye. The same person sees the same thing differently at different times. All those driven or walking past of the end of a series of side streets lit in different ways preferred one kind of source and installation; when they walked into and through these streets the opinion was generally reversed. And the same lighting is seen, used, and appraised by different eyes in very different ways: the adjoining resident, the pedestrian strolling along the footpath, the driver looking for a house number, the driver rushing through, the child running across. More of the population are regarding street lighting from the point of view of drivers; but some drivers are sensitive to the lighting and want it high class in every stretch; others don't worry except at junctions; others are concerned with blind junctions and sharp bends and the entrance to their own garage. Criticisms of the lighting of a whole town may be an enlargement of an aspect of a few streets actually observed.

Likes And Dislikes
The variety in the minds with which observers look at a lighted street makes it often difficult to draw any conclusion about an installation from opinions collected in a questionnaire. Among the factors in the installation affecting liking a colour of light, brightness of source and shape of lantern. The reaction to coloured lighting in many towns is probably different from what itwas five or even two years ago, because more people are accustomed to discharge lighting.

Claimants
The claimant for damages for accident alleged to be due to insufficient lighting have to be seriously considered by the lighting department.

Seeing And Looking
By good lighting we enable people to see; but we cannot ensure that they will even look. To observe requires not only retina but brain; and the brain may be otherwise engaged. Accident may be avoidable by improvement of the lighting; but there are these other factors. So efforts to improve seeing are helped, by road-alterations and, for making the right movement, by various teachers of Safety First to children and grown-ups.

Good Lighting And Other Factors
We thoroughly believe in the value of good street lighting to aid safety and comfort; but we must reject assertions that every night accident is due to lack of light, especially in this city where we are liable to claims for tripping over things, for being run over, for running into things.

Lighting And Accidents
Lighting may be erected to reduce accident but fail according to statistics, from growing traffic and other causes. Yet that lighting may have clearly made the street more comfortable to the user, may have given less chance of accident and certainly less fear of accident - and less opportunity for blaming accident upon the lighting. Analysis of our Chief Constable's report on fatal street accidents reveals that most of these occur in main thoroughfares; but suggestions from police or others than incomplete safety there is associated with poor lighting become few, as to be expected since most of these have been given Group A lighting.

Pedestrians And Residents
A much larger proportion of our complaints and requests in Glasgow is concerned with residents and pedestrians as such in the immediate neighbourhood of their homes than one might expect from a perusal of the usual discussions before technical bodies on the chief factors and requirements in good street lighting.

Mr. J. M. Ward
Tuesday, September 5th, 1939

Mr. A. V. Horsfall
Wednesday, September 6th, 1939

Mr. K. Sawyer
Wednesday, September 6th, 1939

Mr. F. F. Middleton
Wednesday, September 6th, 1939

Mr. F. X. Algar
Friday, September 8th, 1939

Mr. L. J. Davies
B.T.H Co. Ltd.

Friday, September 8th, 1939