The series of lanterns illustrated on the following pages have evolved as a result of years of experience and research. The types of "WEMBLEY" Lanterns hitherto in use incorportated a number of exclusive features connected with ventilation and light distribution, but in the new models important changes have been introduced. When "WEMBLEY" Lanterns were first placed on the market some years ago it was essential for the actual lamps to be kept reasonably cool. Now, however, the OSRAM G.E.C. Lamp Works are able to produce 100/1500-watt gasfilled lamps which have given under test such satisfactory results as to enable them to be used in non-ventilated type lanterns. The efficiency of the latest OSRAM Gasfilled Lamps is in no way impaired by the additional heat to which they are subjected in these lanterns.

These new types of Totally Enclosed "WEMBLEY" Lanterns are practically dustproof, and the efficiency of the light source cannot easily become impaired by the accumulation of dust, dirt or other light obscuring factors on the interior surfaces of the lanterns. Another important consideration is that the amount of cleaning necessary for maintaining the light-giving efficiency is reduced to the minimum.

In the new Totally Enclosed types of "WEMBLEY" Lanterns the fact that the interior only requires occasional cleaning, even in industrial smoke-laden areas, ensures a large saving in general maintenance, the occasional wiping of the outer globe being all that is necessary to maintain for lengthy periods the maximum illumination.

Certain models of the new range of Totally Enclosed "WEMBLEY" Lanterns can be supplied with either symmetric or asymmetric single piece patented glass refractors to suit the particular requirements of given streets.

The advantages of asymmetric distribution for the lighting of narrow thoroughfares are manifold especially when the standards are widely spaced and low mounting heights only are available. Asymmetric distribution provides light up and down the length of the roadway rather in a circle, with the result that the intensity over the area midway between the standards is increased. An important point to be noted in regard to this form of lighting is that the lanterns must be rigidly attached to the supporting brackets or span wires. This is necessary in order that the elliptical field of light shall be of fixed limits in its relation to the direction of the thoroughfare. From the foregoing it will be noted that the bulk of light is directed on to and along the length of the roadway, and in narrow thoroughfares less light is wasted than is the case with symmetric refractors which give a circular field of light, some of which is often distributed over areas which it is not desired to illuminate, such as facades of buildings or fences, hedges, etc.

Special attention is directed to the new form of ribbed outer globe, which is supplied with the 300/500-watt lanterns equipped with asymmetric refractors.

This globe not only improves the appearance of the lantern when viewed at close quarters, but is also of considerable value in the obtaining of a more uniform brightness of the road surface. Its introduction constitutes yet another, but by no means unimportant, advance in G.E.C. Street Lighting Equipment.

Every new Totally Enclosed "WEMBLEY" Lantern is now despatched with full instructions, showing the method of setting the refractors to obtain the best light distribution, and also giving all focusing details.