Wilkinstown wrote:If you look at the signalling diagram for Manulla Junction at
http://catalogue.nli.ie/Record/vtls000306641, you can see that the subsidiary signal (No 26) sited to the
left of the up home signal (confirmed by the photograph at
http://catalogue.nli.ie/Record/vtls000306950) actually reads to the loop despite this being geograpically to the right.
I am now inclined to think that the arrangement of the up home signals at Claremorris (as in the early 1960s) is similar to that which applied at Manulla around the same time. The subsidiary signal simply read to the lower speed route. At Claremorris, I now suspect that the subsidiary home signals at the west end of Claremorris read to the slower route only. This is different to the arrangement which applied at crossing points on the former double line segments of the midland main line where, post singling, the subsidiary signal could read to either the main or loop lines. As I mentioned before the main home signals at these stations could not be lowered unless the main starter had already been lowered. The main starter in turn could not be lowered unless the section token had been released.
Firstly I fail to see how you can deduce , in the absence of any other information that #26 reads to the loop.
You are making a contradictory statement here. If the main signal read to the direst fastest route , irrespective of the physical orientation of the mini dolly , then your second comment about interlocking with the starter makes no sense. No semaphore system I'm aware of , would force a train to remain at the home , until the block ahead was cleared. It was the whole reason rule 39 existed. If you read the mini dolly signal as a simple junction signal , you must be able to apply " checking of trains " to the main signal. Otherwise a train using that line into the station , signalled by the main signal arm would be prevented from drawing into the station, until any train n the forward block section had cleared that block !!! ( that was not the case )
Furthermore , while many web and Thompson machines were so fitted, there is no evidence that the claremorris starters were interlocked with the staff machines. The staff machines had no key release ( electrical release was not used as the dept of P & T maintained the ETS machines and lines in Ireland unlike the U.K. ) and as a result , the ets machine were largely hand generator powered to the very end of their existence , which precluded any form of electrical interlock . The normal approach followed was to have the release of the staff , also allow a key to be released , which could then be used to release the starter , this was common but not ubiquitous.
I suggest that pre a change of purpose sometime in the 60s as a result of an accident , the sgnal main arm was read to both last lines as did the calling on arm. This would allow interlocking of the starter to the home , while still allowing trains to enter station limits , on either line , by aplication of the calling on arm. ( I believe the incident at manulla , if it actually occurred there ? , was more likely that the calling on arm was lowered but the route was incorrrctly set , running the appraching train, that the driver habitually would have entered into the free road , onto a road occupied and the driver , couldn't then stop in time
( note that previously I was told that this incident had cured at claremorris , in neither case can I find any report that mentions it )
Post sixties CIE , I believe , retasked the same signals to mean simple loop,signals and the signal acted as you described in your first paragraph. I.e. The dolly read to the " loop " , irrespective of the physical side it was on the post. This would have meant that the interlocking was modified to allow the main signal to be pulled off even with the starter " on" to allow the train signalled by that arm to enter the station under rule 39 ( or its Irish equivalent ) . CIE in the late 80 s then replaced that physical post with a conventional junction dolly signal that match its purpose.
Hence I would conclude that the original purpose of the signals as well nstalked by the midland and continued on into gsr and early CIE days was that such , signals , i.e. The main arm read to either line and were so interlocked with the starter , and that the calling on arm was then used to draw trains into the station on either line.
What I still find perplexing , is that the Odea photographs of claremorris , show the cabin diagram with the mini dolly to the right of the post , while the signal itself had the dolly isto the left In my experience cabin diagrams were always corrected to respresebt what was actually outside the windows. I cannot square this anomaly