QUOTE (John Webb @ 1 Oct 2019, 09:38)
<{POST_SNAPBACK}>As we understand it, it was what told the 'Fogman' what the signals were showing so he could place detonators appropriately. No idea at present which company it is from; we hope our member we got it from can tell us in due course.
Regards,
John
Thanks John
That makes the device a Fog Signalman's signal indicator. I suspect that they tended to be provided by the signal manufacturing companies rather than made by the railway companies. They were predominantly installed where there was heavy traffic so that the Fog Man had quick information about the signal indication. This also meant that they tended to be at the locations that had detonator placers - which were installed to reduce the risk of Fog Men getting hit by trains (rather than to avoid any danger from the detonators themselves - railway "dets"/fog signals were substantially safe).
Where there were multiple tracks (and the various signals for them) both indicators and det placers could be located in safe positions - usually to the side of the track in the cess area. This meant that one fog man could signal a number of lines and not have to cross or get near the track.
I think that these indicators were made more necessary by Upper Quadrant signals - because their counterweight was usually close to the top of the signal where it couldn't be seen in a fog. With a Lower Quadrant signal the counterweight was normally at or near the base of the post making it possible to be seen by the Fog Man - also by train crew at the signal.
I knew Southern Drivers who had had to climb signal ladders to discover the position of the UQ signal arm during "pea soup" fogs in the 1950s and 60s.
There were many designs of det placer. Some of them were "single shot" that had to be reloaded each time - others had a magazine and a mechanism to feed the next det into the holder that put them on the rail head.
At one (I think early) stage the practice at some places (?on some companies?) two detonators a number of feet apart were used for fogging. This was to ensure that at least on should go off (i.e. the dets were less reliable at that time). In order to not waste a second det when the first exploded there was a device that would lift the second det if/when the first went off - the "blast" from the first being enough to flip the mechanism and move the second. This had a single det holder at each end of a rod mounted beside the rail. The device presumably had to be kept well lubricated. It would have had the advantage that, if the first det did blow the second could be put back on the rail as soon as the train had cleared - meaning that there would be a t least one det in place almost immediately. As far as I know these devices were never used with magazine placers.
Fogging was a cold, wet, horrible job that could last for days. Fog huts were not always provided and those that were ,were usually small and not necessarily much use. Even if they did have a small iron stove the fog man had to acquire fuel for it - which may well have been a lump or two of coal from loco crew in steam days... A good reason to keep friendly with loco crew - especially if they might not bother to slow down to deliver the lumps of coal. Where there was an indicator I might suspect that a fog man might find a way to sit an empty bean tin (or similar) on the top of the indicator arm so that it would fall off and clatter when the signal aspect changed - this might allow him some rest from observing the indicator and, possibly, let him get into a little shelter.
When dets are used for other purposes (except train protection) - such as flagging signals - their use is known (unofficially) as "banging down" - i.e. providing a caution signal to train crew.
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