Acme Thunderer Whistle Numbers and Uses

Hi all
A question coming from a colleague of mine who has acquired an Acme Thunderer Whistle stamped with GWR on one side and P.WAY 2785 on the other (see photos), and was asking me what I knew about potential uses of it relating to the P-Way department and whether there was a significance of the number
Doing a google search for Acme Thunderer Whistle Numbers reveals a number that have been sold on various railwayana auction sites each with P.WAY but different company names and numbers stamped on them (e.g. Barry Railway 193, Rhymney Railway 191, GCR 887 etc).
So, first of all, does anybody know if there is a significance to the numbers in this case - was this a client number or order number put on by the manufacturer, or were the numbers determined by the railway companies for certain purposes? Does this link the whistle to use in a certain part of the GWR network or even a specific location or employee?
Secondly, were Acme Thunderers like this used as warning whistles for P Way gangs (I had thought it was more horn-like things used in these purposes) or is it something like guards whistles were also marked as PWAY even though they weren't used by the PWAY department? Or something else altogether?
Many thanks for any light you can shed on this

 

You could always ask the manufacturer:
www.acmewhistles.co.uk
They have a question & answers section or write to them at:

J. Hudson and Co. (Whistles) Ltd.
244 Barr Street
Birmingham
B19 3AH
UK

Tel: 0121 554 2124

 

I'm 99% sure I've come across whistles used by p.way lookouts, although I can't remember when or where it was. Horns more common these days, certainly, but I'd be fairly confident that that's who would have used these. What the numbers mean, I have no clue.

 

Horns and whistles both issued to Lookouts, either may be used but agreed at start of work method of warning used.
Both Whistle and Horn last used by me on Network back in 2010 but more recently on NYMR.

 

Very useful for those difficult phone callers.

 

I used my Acme Thunderer for many years directing the wayward (pedestrians and motorists) in Toronto. Now I use them as the conductot(guard) on the Golden Horseshoe Live Steamers. Look us up if you are in the area
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