This catalogue from September 1920 introduced an entirely new range of well-glass lanterns; none of the lanterns
offered in the 1914 catalogue were continued. Further changes included the introduction of polar diagrams
to explain the various distributions (a factor not mentioned in 1914), space-height ratios, the emergence
of the idea of lanterns working in pairs, and, most importantly, the first use of a Holophane refractor bowl.
Some of these ideas were described in a letter included in the catalogue:
INDUSTRIAL AND STREET LIGHTING
The development of the Gasfilled Electric Lamp and the great strides made in the field of Illuminating Engineering have,
during the past few years, entirely revolutionised methods of lighting and have rendered obsolete the old fashioned "rule of thumb"
procedure for planning lighting installations.
We have made a careful study of lighting questions with the result that we have produced complete ranges of lighting units of
the very highest order, designed on correct scientific principles. These are shown in our new Industrial and Street Lighting Fittings
Catalogue, Section F.1., a copy of which we have the pleasure to forward herewith.
In addition to much valuable technical data, particulars are given of robust fittings suitable for work lighting and many designs of
Street Lanterns. Of the latter, we would commend to your special notice the "City" and "Metropolitan" lanterns, full particlars of which
are given on pages 986 to 989. These are specially suitable for lighting on main thoroughfares.
The last paragraph quoted is also especially telling, as it's the first indication of the separation of main road lighting and
I have also included the section on the Illuminating Engineering Data. It is mainly concerned with interior lighting, but some
of the concepts are applicable to street lighting, and, at the time, the two were not separated. So, rather than try and pick out the
street lighting data, I've added the whole section.
Section 1. Industrial Lighting
Section 2. Street Lighting
- Benjamin Reflector Fittings For Direct Lighting: Distributing Type (Page 962)
- Benjamin Reflector Fittings For Direct Lighting: Concentrating Type (Page 963)
- Benjamin Reflector Fittings For Direct Lighting: 45° Angle Type (Page 964)
- Benjamin Industrial Lighting Fittings And Reflectors (Page 965)
- Benjamin Steel Reflectors For Local Lighting: Extensive, Intensive And Angle Types (Pages 966-967)
- Industrial Fittings Semi-Indirect (Pages 968-969)
- Industrial Fittings Indirect (Page 970)
- Hand-Lanterns (Page 971)
- Well-Glass Fittings: China Watertight (Page 972)
- Well-Glass Fittings: Cast Iron Watertight (Page 973)
- Bulkhead Fittings (Page 974)
- Accessories (Page 975)
- Conical Shades (Page 976)
- Counterweight Sets (Page 977)
- Wood Blocks (Page 978)