B&W levers in Quorn box?

There are two black and white levers in Quorn Signal Box on the Great Central. I simply want to know - what is their function? :noidea:

Here there are some shots of the frame from John Tilly's incredible site. http://tillyweb.biz/gallery/qq/quorn.htm which show the frame and the diagram, where the levers 5 and 25 (the B&W ones) are next to two lines perpendicular to the line on the Up and Down Mains.

 

im no expert but i think they are for detonators.

 

Black and White Chevrons = Detonator Placers. Chevrons pointing up for Up lines, pointing down for Down lines.

 

Yes - detonator placers. These are 5 and 23 on the diagram - just visible as two small black dots above each of the running lines above the red/white rectangle showing the signal box on the diagram.

The placers swung out the detonators onto the railhead when the lever was pulled. The detonators were fitted with a special clip on the side, not the usual lead straps, for the machine to hold them. Some versions of the placers had magazines which recharged the placer if the detonators were used.

At St Albans South we have 4 of these levers, one for each line. The levers are not interlocked with any other lever so they can be instantly pulled in any emergency.

 

Fitted to boxes following one of the recommendations made by the Inspecting Officer investigating the Ais Gill accident; September 1913.

 

Thanks everyone for your answers. Are the levers just for show or are detonators actually fitted?

 

Not sure what the point of them are if they are actually used to place detonators on the line. Railtrack/NR did away with them in most boxes years ago.

 

I believe I'm right in saying (I'm sure I'll be corrected quick enough if I'm wrong) that AWS and colour light signalling made them less important. Weren't they used to provide an indication of the position of signals in fog?

Steve B

 

You may be thinking about fog signalmen regulations when a detonator was laid at distant signals during thick fog. I believe the detonator levers were to be used in an emergency to alert drivers to imminent danger.

 

Quite correct. Many distant signals were converted to colour light signals to avoid the need to send someone out in foggy weather. We've recently found out the distant signals at St Albans South were converted from mechanical ones before WW2. Not only did such a conversion save money on eliminating a fogman, but it also cut out the costs of maintaining over a mile of wire to each signal and their supporting infrastructure, ie all those lineside pulleys!
The emergency detonator placers remained in use until the box closed in December 1979

 

For the reasons WHY they were introduced - don't speculate - read the Ais Gill accident report !

 

Thanks for that - yes, I probably was thinking of that!

Steve B

 

Levers are full operational.
You can see the signalman loading the apperatus in the morning before the first train if you get there early

 

http://www.railwaysarchive.co.uk/documents/BoT_AisGill1913.pdf

Lengthy, but a very clear analysis of what went wrong, why and how, plus very clear descriptions of lessons to be learnt. In fact, typical of railway accident investigation reports, from Victorian times to the present day.

 

One unusual placement of a detonator placer was at London Bridge before the latest refurb. In the 70s or may have been 80s a through road was addedalongside P7 when the platforms were still numbered 1,2,3,4,6 and 7.P 5 had been a through road taken out when 10 cars were introduced. To allow the loop to join theplatform 7 road the starter was moved back. As it was no longer at the end of the platform there was a SPAD risk of a local overshooting and side swiping an express ( yes I know this is the southern). A detonator placement mechanism was conected to a ground dolly mech, no disk, and worked in conjunction with p7 starter. When the starter was on the dets were placed on the track. When the starter had a proceded aspect the dets were withdrawn

 

@threelinkdave, I remember seeing a training film made before WWII (I think it was by the LMS) on the subject of SPADs; according to the narrator, the majority of SPADs were down to two causes;
1. a signal, such as an inner home or a platform starter, being pulled off, and the driver assuming that the signal in advance had also been pulled off, and going past it without looking;
2. a driver getting the right away from the guard, and not checking that the platform starter had been cleared.

(in fairness to the guards, the rule book was very clear that the right away only told the driver that platform duties were complete - it was still the driver's responsibility to check and obey the signals; platforms built on a curve which meant the guard couldn't see the starter sometimes had a repeater for him to check, but even that didn't relieve the driver of the responsibility of checking for himself)

That being so, I can see that the possibility of a local service sideswiping an express at that location was a very real danger - and the system used to guard against it that you've described was a very neat way of doing the job, with minimum work and cost.

 

A couple of drawings of a det placer below: