Thorn Beta 7

Lantern acquired in March 2007.

A 'proper' Thorn lantern now - and another to tick off my 'Beta' list - just the 1, 3, 6 and 9 left to get hold of now! This example also came from the cemetery where my older Gamma 5 came from - hence why it hadn't been replaced years ago. The last Beta 7s on public roads in Derby were removed in the early-mid 1990s on the Silverhill estate in Mickleover, however several privately-owned examples continue to run in Darley Abbey - see here.

The Beta 7 can be distinguished from lanterns such as the GEC Z8896 and AC Ford AC850 by its shallower canopy and by the fact that the lamp is in a more recessed position. Unfortunately the glass bowl on this example is cracked and so a new one will be required.

The damage can easily be seen at this angle. A Philips lamp is employed but it is a modern HPL-N rather than the vintage 'Powerwhite' which came with the Gamma 5.

 The canopy is in excellent condition - the aluminium is free from any visible corrosion.

The same cannot be said for the bowl support ring - corrosion has certainly set in on this.

The lantern is reasonably clean internally even though the gasket is missing.

There are only some small flecks of dirt in the bowl.

The lantern was operated by an all-night Venner MS2SP time switch. The ballast seen here dates from the early 1980s and could possibly be original.  A capacitor was also included.


The inside of the lantern was cleaned and repainted on Saturday, 28th June 2008. The two pieces of bowl were also cleaned up and then slotted back together. The lantern was then reassembled and installed on an AC Ford AC872 wall bracket, behind the GEC 'Clearmain' Difractor lantern.

The lantern was then powered up:

Lantern warm-up video:

Thorn Johanna 1 | Simplex Lucidor




© 2002 - English Street Lights Online