Signalling a Swing Bridge

[PFX]

I'm having a quandary on a section of line I'm working on, namely Clachnaharry swing bridge west of Inverness. I can't seem to find any evidence that there were or are signals approaching the bridge but this seems odd given the risk when the bridge span is open. Anyway, I've signalled it with a distant and home semaphore on either side of the bridge.

The problem in doing so, is that I don't know how the signal box controlled the semaphores on the opposite side of the canal. In reality, was this achieved electrically? As I'm including trackside signal wires, it would be quite handy to know.

Thanks,
Innis

[ScottAS2]

The problem in doing so, is that I don't know how the signal box controlled the semaphores on the opposite side of the canal.

This is entirely supposition, but it'd surely be possible to pass some sort of mechanical linkage - a push-rod, say - through the bridge joint(s)? That'd also have the advantage that it'd fail right-side if the bridge was opened without the signalman placing the protecting signals on.

[edit]Actually, second thoughts: possibly there aren't any signals at all: the Far North Line's mostly single track, so possibly safety is assured by posession of the token (presumably interlinked in some way with the bridge controls, so that the bridge has to "posess the token" to open).

[clam1952]

Found this: signal visible here https://www.railscot.co.uk/locationnew. ... tographer=

[ScottAS2]

Found this: signal visible here https://www.railscot.co.uk/locationnew. ... tographer=

Well, that puts paid to my token idea! Well spotted.

[ScottAS2]

I'm pretty sure I've found it! This picture of what's labelled the "locking mechanism" is, I suspect, at least in part the signalling system. You can see in this and especially this photograph how there's a set of rods passing across the bridge from some sort of "cable troughs" on either side, and in the main picture you can see how each of the two rods engages with its counterpart the other side of the join. We know from the box's listed building entry that the signals and the bridge locks are controlled separately, so I think the leftmost part must somehow control the bridge lock, which I guess is the large square-footed thing centre-left (or maybe just unlocks the lock - the bridge was originally entirely manually operated, and modern photos show what looks to be a locking mechanism in the four-foot, which doesn't seem to be present in these historical photos, while the right rod will go on to control the signal on the far side of the bridge (which the geometry shows must be the side the photo was taken on).

[PFX]

Thanks guys. My query is partially answered. I'd never noticed signals in photos before but now I know they existed. Not sure that the rods were part of the signalling though but to be honest, it won't really matter as I can 'wing it'.

[Chris1955]

There was an article in the Railway Magazine back end of 2015 about the railways of Norfolk. ( Norwich - Yarmouth - Lowestoft). Within the article mention was made of (if memory serves me correct of location) Somerleyton swing bridge. The signalman was stated as saying the signals on the far side of the bridge was a hard pull as they were operated by point rodding, as it wasn't possible to put signal wires through the bridge.

Hope this answers your query.
Chris A.

[PFX]

Thanks,

Seems to confirm Scott's earlier answer.

Much obliged.