Re: Signalling in Victoria

[David Langley <del@ancc.com.au>]

Eddie Oliver wrote:

> I thought the main purpose of the control was to ensure locking between
> the two opposing directions - i.e. to prevent a train being admitted to
> the Showgrounds platform from the Newmarket end while simultaneously one
> was being admitted from the Racecourse end. In other words, it provides
> a sort of central interlocking between the two separate signal boxes,
> which would otherwise have required some direct interlocking between
> them.
>
> Contrary to what someone else said, this IS clearly documented in the
> instructions for the Racecourse line. It includes instructions that when
> leaving the Rostrum unattended, the signaller must ensure that the
> control lever is left in the position which allows the platform track to
> be used as the normal direct route from Racecourse towards Newmarket, as
> one would expect.
>
> I do not understand why it had to be a full GRS or GRS-like lever rather
> than just a simple three-position toggle switch.

Yes you are correct. I have just found my copy of the instructions and that is precisely it.
It appears that there was no locking between Box H and Showgrounds Junction for moves to the
Showgrounds platform. It was probably a GRS style simply because there was one available at
the time and it appears to date from around 1930. The 1929 litho does not show it but the 1935
litho does. It suggests that there might have been a near miss or something. In the mechanical
days, there were more home signals in the area and they all appear to be track controlled and
thus there was probably a common track section somewhere that prevented opposing moves. If a
circuit diagram turns up for the era the question will be answered. Track locking on the line
came on 31 October 1910 and power signals on 5 July 1919.